Answer:
88
Explanation:
The ion has a charge of 2+, therefore the number of neutrons it possess is 86+2
which equals 88
The element X having a mass number of 230 and has 86 electrons is radium and has 142 neutrons.
An atom is composed basically of electrons, protons and neutrons. In a neutral atom, the number of protons and electrons are equal. The number of neutrons is the difference between the mass number and the number of protons (atomic number).
Since we know that the ion of the element X has 86 electrons and the compound formed is XBr2, it then means that neutral X has 88 electrons.
The number of electrons in the neutral atom is the same as the number of protons or atomic number. An element can be identified by its atomic number. The element having atomic number 88 is radium.
The number of neutrons is obtained as;
Mass number - atomic number
230 - 88 = 142 neutrons
Learn more: https://brainly.com/question/803445
11. Samantha was asked to measure out 10 g of salt in a lab. She mistakenly measures out 15 g instead. Calculate
the percent error. Make sure your answer has the correct number of significant figures!
Answer:
50%
Explanation:
Expected measurement required = 10g
Actual measurement observed = 15g
The percentage error is given as proportion the difference between the actual and expected measurement or values and the expected value value expressed as a percentage.
[(Actual - Expected) / Expected] × 100%
[(15 - 10) / 10)] × 100%
(5 / 10) × 100%
0.5 × 100%
50%
Therefore, the percentage error in the measurement is 50%
clearly distinguish between science and technology
Answer:
The words science and technology can and often are used interchangeably. But the goal of science is the pursuit of knowledge for its own sake while the goal of technology is to create products that solve problems and improve human life. Simply put, technology is the practical application of science.
Explanation:
Check the following images
Hope it helps!!!
Please mark it as Brainliest ( the crown icon)
if 193 ml of chlorine gas was collected at 21 celsius, what volume would it have if the temperature dropped to 0 celsius
Answer:
New volume of chlorine gas (V2) = 179 ml (Approx)
Explanation:
Given:
Volume of chlorine gas (V1) = 193 ml
Temperature of chlorine gas (T1) = 21°C = 21 + 273 = 294 k
New temperature of chlorine gas (T2) = 0°C = 0 + 273 = 273 k
Find:
New volume of chlorine gas (V2) = ?
Computation:
Using charle's law
V1 / T1 = V2 / T2
193 / 294 = V2 / 273
V2 = 179.21
New volume of chlorine gas (V2) = 179 ml (Approx)
formula for soda glass
Answer:
composition of soda-lime glass is 73% SiO2 – 15% Na2O − 7% CaO − 4% MgO − 1% Al2O3 [129,132,133].
The Soda glass formula is SiO2, Na2O, CaO, Al2O3, K2O, SO3, MgO, Fe2O3, TiO2
Soda glass is a chemical compound that stands out for being the most widely used material to make windows, bottles, glasses, among others.
This compound is characterized by being chemically stable, reasonably hard, and extremely versatile because it can be recycled since it can be melted to make new products.
Its chemical formula is made up of other compounds such as:
SiO2, is Silicon OxideNa2O, is sodium oxideCaO, is calcium oxideAl2O3, is aluminum oxideK2O, is potassium oxideSO3, is sulfur oxideMgO, is magnesium oxideFe2O3, is iron oxideTiO2, is Titanium OxideAdditionally, the compounds found in the highest proportion in glass are SiO2 (74 atoms) and Na2O (13 atoms).
Learn more in: https://brainly.com/question/1247523
What three things are required for a fire to start?
Polymers formed from amino acids are called _____. proteins carbohydrates lipids nucleic acids
Answer:
Proteins
Explanation:
Amino acids act as monomers (a single unit used to form polymers) , the polymer will be a long chain of individual amino acids. An amino acid chain forms a protein. These proteins are also known as peptides.
Hope this helps and please mark as the brainliest.
What are half reaction
Answer:
When you don't have a complete reaction.
Explanation:
Happens a lot between a solvent and a solute. The solute may not bind well with the solvent I.e. water.
Which of the following is NOT a product of the electrolysis of NaCl? A. Chlorine gas B. None of these C. Hydrogen gas D. Oxygen gas
Answer:D. Oxygen gas
Explanation: because the experiment showed
If you have a little air in a balloon, find the volume of the balloon if the mass is 0.6 g and the density of the air is 0.0012 g / mL
Hey there!:
Mass = 0.6 g
Density = 0.0012 g/mL
Volume = ??
Therefore :
Density = mass / Volume
0.0012 = 0.6 / V
V = 0.6 / 0.012
V = 500 mL
Hope this helps!
What mass of Fe(OH)3 is produced when 35 mL of 0.250 M Fe(NO3)3 solution is mixed with 55 mL of a 0.180 M
KOH solution? (this is a limiting reactant problem).
Answer:
0.35 g.
Explanation:
We'll begin by calculating the number of mole of Fe(NO3)3 in 35 mL of 0.250 M Fe(NO3)3 solution.
This is illustrated below:
Molarity of Fe(NO3)3 = 0.250 M
Volume = 35 mL = 35/1000 = 0.035 L
Mole of Fe(NO3)3 =?
Molarity = mole /Volume
0.250 = mole of Fe(NO3)3 / 0.035
Cross multiply
Mole of Fe(NO3)3 = 0.25 x 0.035
Mole of Fe(NO3)3 = 8.75×10¯³ mole
Next, we shall determine the number of mole of KOH in 55 mL of 0.180 M
KOH solution. This is illustrated below:
Molarity of KOH = 0.180 M
Volume = 55 mL = 55/1000 = 0.055 L
Mole of KOH =.?
Molarity = mole /Volume
0.180 = mole of KOH /0.055
Cross multiply
Mole of KOH = 0.180 x 0.055
Mole of KOH = 9.9×10¯³ mole.
Next, we shall write the balanced equation for the reaction. This is given below:
3KOH + Fe(NO3)3 —> Fe(OH)3 + 3KNO3
From the balanced equation above,
3 moles of KOH reacted with 1 mole of Fe(NO3)3 to produce 1 mole of Fe(OH)3.
Next, we shall determine the limiting reactant. This can be obtained as follow:
From the balanced equation above,
3 moles of KOH reacted with 1 mole of Fe(NO3)3.
Therefore, 9.9×10¯³ mole of KOH will react with = (9.9×10¯³ x 1)/3 = 3.3×10¯³ mole of Fe(NO3)3.
From the above illustration, we can see that only 3.3×10¯³ mole out of 8.75×10¯³ mole of Fe(NO3)3 given is needed to react completely with 9.9×10¯³ mole of KOH.
Therefore, KOH is the limiting reactant and Fe(NO3)3 is the excess reactant.
Next, we shall determine the number of mole of Fe(OH)3 produced from the reaction.
In this case, we shall use the limiting reactant because it will give the maximum yield of Fe(OH)3 as all of it is consumed in the reaction.
The limiting reactant is KOH and the mole of Fe(OH)3 produce can be obtained as follow:
From the balanced equation above,
3 moles of KOH reacted to produce 1 mole of Fe(OH)3.
Therefore, 9.9×10¯³ mole of KOH will react to produce = (9.9×10¯³ x 1)/3 = 3.3×10¯³ mole of Fe(OH)3.
Finally, we shall convert 3.3×10¯³ mole of Fe(OH)3 to grams. This can be obtained as follow:
Molar mass of Fe(OH)3 = 56 + 3(16 + 1) = 56 + 3(17) = 107 g/mol
Mole of Fe(OH)3 = 3.3×10¯³ mole
Mass of Fe(OH)3 =?
Mole = mass /Molar mass
3.3×10¯³ = Mass of Fe(OH)3 / 107
Cross multiply
Mass of Fe(OH)3 = 3.3×10¯³ x 107
Mass of Fe(OH)3 = 0.3531 ≈ 0.35 g.
Therefore, 0.35 g of Fe(OH)3 was produced from the reaction.
A compound that has a sea of delocalized electrons has what type of bonding?
Answer:
Metallic Bonding
Explanation:
Metallic Bonding
In metallic bonds, the valence electrons from the s and p orbitals of the interacting metal atoms delocalize. That is to say, instead of orbiting their respective metal atoms, they form a “sea” of electrons that surrounds the positively charged atomic nuclei of the interacting metal ions.
Which element increases its oxidation number in this reaction? 3KOH + H3PO4 → K3PO4 + 3H2O
Answer:
The answer is "no changes in oxidation number "
Explanation:
Given equation:
[tex]3KOH + H_3PO_4 \longrightarrow K_3PO_4 + 3H_2O[/tex]
In the above-given equation, there are no changes in the oxidation number which can be defined as follows but first we defined the oxidation: In the chemical process, it requires the transfer of ions is oxidation. In particular, it means that products that supply electrodes are oxidized. In the given equation, when 3Potassium hydroxide reacts with phosphoric acid it will produce potassium phosphate and 3 moles of water.
How does the percentage of monounsaturated and polyunsaturated fatty acids in olive oil compare to that of canola oil? Match the words in the left column to the appropriate blanks in the sentences on the right. Make certain each sentence is complete before submitting your answer. ResetHelp Olive oil has about Olive oil has about blank monounsaturated fats, while canola oil has about blank. monounsaturated fats, while canola oil has about Olive oil has about blank monounsaturated fats, while canola oil has about blank.. Olive oil has about Olive oil has about blank polyunsaturated fats, while canola oil has about blank. polyunsaturated fats, while canola oil has about Olive oil has about blank polyunsaturated fats, while canola oil has about blank..
This question is incomplete, here´s the complete question.
How does the percentage of monounsaturated and polyunsaturated fatty acids in olive oil compare to that of canola oil? Match the words in the left column to the appropriate blanks in the sentences on the right.
Olive oil has about ____ monounsaturated fats, while canola oil has about ___.
Olive oil has about ___ polyunsaturated fats, while canola oil has about ___.
6%
10%
30%
84%
5%
65%
Answer:
Olive oil has about 84% monounsaturated fats, while canola oil has about 65%.
Olive oil has about 5% polyunsaturated fats, while canola oil has about 30%.
Explanation:
Olive and canola oil are the major sources of monounsaturated fatty acids. Although vegetable oils usually have high concentrations of polyunsaturated fatty acids and less monounsaturated fats, olive and canola oils have comparatively less polyunsaturated fatty acids, and more monounsaturated fatty acids.
Does Na2 gas posses metallic character? Explain your answer..
Explanation:
It contains Na2 molecules and the atoms in this molecule are held together by a purely covalent bond because the electronegativity of the two atoms is identical.Metallic bonding would not kick in until you make clusters of quite a few atoms. Such clusters would likely not be very stable because thermodynamically the larger the clump of material the more stable it gets. So they tend to coalesce until you have chunk of metal.Metallic bonding is in a sense a form of covalent bonding, but it is very collective (delocalized over a great many atoms) and electron deficient (there are more states than electrons to fill them up with, leading to conductive properties. This means that “a metallic bond” is a bit of an oxymoron like a forest with only one tree.Reply me in commentsYes, Na2 gas possesses a metallic character.
Does NA contain metallic bonds?In the stable state, metal sodium functions as an array of Na+ ions which can be surrounded by way of a sea of 3s electrons. However, it would be wrong to consider metal sodium as an ion when you consider that the ocean of electrons is shared by using all of the sodium cations, quenching the nice fee.
Sodium most effective has one valence electron. So, in metallic bonding, it is able to only donate one electron to be delocalized at some point of the structure. In steel bonding, the real bonding is the electrostatic force between the effective cations and the delocalized electrons.
Learn more about metallic bonds here: https://brainly.com/question/20536777
#SPJ2
1.) Given 30 grams of CO2, how many moles of CO2 would you have? How many individual molecules of CO2 is that?
2., Given 22 Grams of NaCl, How many moles of Nacl would you have? How many individual molecules of NaCl is that?
3.) Given 50 grams of ammonia NH3, How many moles of NH3 would you have? How many Molecules of NH3 is that?
Answer:
1a) .68 moles 1b)4.1E-23 molecules.
2a) .37 moles 2b) 2.27E-23 molecules
Explanation:
1a) CO2 is equal to 44 grams (C→12 grams,O→16 grams[·2]) .30g/44g is .68 moles.
1b) multiply 1A by advogadros number (6.022E-23)
2a) NaCl is 58 grams. 22/58 is .37 moles.
2b) multiply 2A by advogadros number.
you'd answer #3 the same way #1 and #2
The branch of science that deals with chemicals and bonds are called chemistry. The moles are units to calculate the quantity required to use the element.
The correct answer is mentioned below.
What are moles?The mole is the base unit of the amount of substance in the International System of Units (SI). It is defined as exactly 6.02214076×10^23 elementary entities which may be atoms, molecules, ions, or electrons.According to the question, the moles to the option is as follows:-
moles of 30 grams of CO2 is[tex]n =\frac{M}{M.M}\\ \\\frac{30}{44} \\\\=0.681\\\\[/tex]
The number of molecules is [tex]0.68 *6022*10^{23} =4.09496*10^{23[/tex].
2. moles of 22 grams of NaCl is
[tex]\frac{22}{44}\\ \\=0.5\\\\[/tex]
Molecules will be [tex]0.5*6.022*10^{23} = 3.011*10^{23}[/tex]
3. moles of 50-gram ammonia
[tex]\frac{50}{17} \\\\2.94\\[/tex]
The number of molecules is [tex]2.94*6.022*10^{23} = 1770*10^{23[/tex]
For more information about the moles, refer to the link:-
https://brainly.com/question/15209553
Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below. A purple ball in the center surrounded by overlapping concentric black ovals, each with a small green ball on each of the 6 ovals. What experimental evidence led to the development of this atomic model from the one before it? A few of the positive particles aimed at a gold foil seemed to bounce back. The colors of light emitted from heated atoms had very specific energies. Experiments with water vapor showed that elements combine in specific proportions. Cathode rays were bent in the same way whenever a magnet was brought near them.
Answer:
A few of the positive particles aimed at a gold foil seemed to bounce back.
Explanation:
Rutherford's experiment took the search for the structure of the atom a step further. In this experiment, a narrow beam of alpha particles emitted from a source was used to bombard a thin gold foil.
The scattering of the alpha particles was detected by a movable ZnS screen. It was found that most of the alpha particles followed a straight path through the gold foil but some were scattered through large angles and some even scattered backwards.
Following this experiment, Rutherford decided on his planetary model of the atom in which the nucleus is at the core of the atom with electrons moving round the nucleus in orbits. Rutherford was awarded a Nobel prize for this work.
Answer:
a
Explanation:
edge 2020
Choose all the answers that apply
Protons:
Have a positive change
Have no change
Are found in the nucleus
Orbit the nucleus
Have a negative charge
Lavoisier developed a new theory of combustion that overturned the phlogiston theory. What measurements were central to his theory, and what key discovery did he make?
Answer:
Lavoiser proposed a theory in charge of writing the combustion correctly, denying the phlogiston.
Lavoiser said that combustion is carried out in a medium where there is oxygen, giving as a product water and carbon dioxide.
This combustion results in the decrease in the volume of the material that burns.
Furthermore lavoiser discovered the importance of oxygen in animal respiration.
Explanation:
Lavoisier argued that if or if the presence of oxygen must be present, it is an irreversible and spontaneous process.
What is the independent variable of Smithers experience?
Please help controls and variables simpson? Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special...
Answer:
Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're ... Group A is given the special juice to drink while they work. Group ... 1. Control Group. Group B. 2. Independent Variable. volume of special juice.
Explanation:
Answer:
1. Group B
2. The juice
3. The number of stacks of paper
4. the juice did not help improve a quicker process
5. Group A can be given the juice, Group B can be given the juice without the special ingredient
USE QUIZLET FLASH CARDS IT CAN HELP YOU WITH A LOT OF QUESTION
What element is depicted by the following electron configuration:
you can determine this by
adding the numbers of the sub-shells, 2+2+6+2+4=16the number on the last sub-shell, 4 means on the 4th main groupthe 3 before 3p4, tells us on the 3rd period, so the answer is Sulphur.The pOH of a solution is 3.1. Which of the following is true about the solution? (1 point)
It is acidic and has a pH of 10.9.
It is basic and has a pH of 10.9.
It is acidic and has a pH of 6.2.
It is basic and has a pH of 6.2.
Answer:
The answer is option BExplanation:
To solve the question above we must first find the pH of the solution using the formula
pH + pOH = 14
pOH = 3.1
So we have
pH + 3.1 = 14
pH = 14 - 3.1
pH = 10.9
Since it's pH is 10.9 the solution is a basic solution since it's pH lies in the basic region.
Hope this helps you
What is the formula of the ion hydrogen sulfite, which has a charge of -1
There are two types of ions in chemistry, one is cation and the other is anion. Anion is the negative charge ion. Therefore, the formula of hydrogen sulfite ion is HSO₃⁻
What is chemical Compound?Chemical Compound is a combination of ions, ions forms by combination of element and element forms by combination of atoms in fixed proportion.
According to our question the chemical compound from which hydrogen sulfite ion is coming is sulfurous acid that is H₂SO₃. So to get hydrogen sulfite ion we need to remove one hydrogen ion that is H⁺ from the chemical compound sulfurous acid.
The balanced reaction is
H₂SO₃[tex]\rightarrow[/tex]H⁺ + HSO₃⁻
From above reaction we can see that the charge over hydrogen sulfite ion is -1
Therefore the formula of hydrogen sulfite is HSO3-
To learn more about chemical compound, here:
https://brainly.com/question/26487468
#SPJ6
The pH of a solution decreases by 2.0. How does the hydronium ion concentration of the solution change? Increases to 2 times the original concentration increases to 100 times the original concentration decreases to one one hundredth. Of the original concentration decreases to one half. Of the original concentration
Answer:
The hydronium ion concentration increases to 100 times the original concentration
Explanation:
The pH of a solution is defined as the negative logarithm of the hydrogen or hydronium ion concentration of that solution. It is given by the expression below:
pH = -log[H₃O⁺] = log[H₃O⁺]⁻¹
Assuming the solution was at neutral with original pH = 7;
The new pH of the solution will be = 7 - 2 = 5
At pH = 7;
log[H₃O⁺]⁻¹ = 7
[H₃O⁺]⁻¹ = 10⁷
[H₃O⁺] = 10⁻⁷
At pH = 5
log[H₃O⁺]⁻¹ = 5
[H₃O⁺]⁻¹ = 10⁵
[H₃O⁺] = 10⁻⁵
10⁻⁵ = 10⁻⁷ * 10²
But 10² = 100
Therefore, the hydronium ion concentration increases to 100 times the original concentration
Answer:
B
Explanation:
On Edge
Chemistry is often called the __________ science because it involves the study of the materials in the universe and the changes these materials undergo
Answer:
Central
Explanation:
Chemistry is often called the central science because of connects the physical sciences, life sciences and applied sciences.
Chemistry is the study of matter and changes undergone by matter. This makes chemistry to occupy a central place in many scientific disciplines including medicine, engineering, pharmacy, geology etc. Basic knowledge of chemistry is usually required by experts in these disciplines.
Answer it answer it answer it
Answer:
[tex]\Large \boxed{\mathrm{A}}[/tex]
Explanation:
Rust formed from iron and oxygen combining is a chemical change, because in a chemical change, the resulting substance(s) will have different properties from the substance(s) before the chemical change.
I cant comment... So is it Right?
If each geometric shape represents a different type of atom, and atoms that are touching have chemically bonded with each other, which best describes this model? * 1. An element 2. A compound 3. A homogeneous mixture of two compounds 4. A heterogeneous mixture of two compounds 5. A homogeneous mixture of four elements 6. A heterogeneous mixture of four elements
Answer:
The correct option is;
3. A homogeneous mixture of two compounds
Explanation:
An homogeneous mixture is one where the components of the mixture are evenly dispersed such that the individual components cannot be seen to be isolated and distinguishable and having a constant composition of the constituents
The image displays three atoms (red circle, cyan triangle, and orange rectangle). The red circle appear to be bonded in pairs while the cyan triangles are bonded to the orange rectangles making a total of two compounds
The arrangement of the compounds in the mixture appear to be very evenly distributed to suggest an homogeneous mixture
The visibility of the compounds should be for an illustrative purpose.
4. (01.05 MC)
Rubbing alcohol evaporates from your arm quickly, leaving a cooling effect on your skin. How do the molecules of gas compare to the molecules as a liquid? (4 points)
The gas particles move faster, have the same molecular composition, and have weaker attractions between them than the liquid particles
The gas particles move faster than the liquid particles, and the bonds of the molecules are broken during evaporation to allow gas atoms to spread apart.
The gas particles move slower but have the same molecular structure and the same attraction between them as the liquid particles.
The gas and liquid particles move at the same speed, but the bonds of the molecules are broken during evaporation to allow the gas atoms to spread apart
Answer:
The correct option is;
The gas particles move faster, have the same molecular composition, and have weaker attractions between them than the liquid particles
Explanation:
The properties of the gas molecules in comparison to liquids are
1) The gas molecules are widely spread out
2) After evaporation and while in conditions favorable to the gaseous state, the kinetic energy of a gas is larger than the inter molecular attractive forces
3) A gas fills the container in which it is placed
For liquids
1) There are strong intermolecular forces holding the molecules together in a liquid
2) Liquid attractive forces in a liquid are strong enough to hold neighboring molecules
3) The volume of a liquid is definite.
how many significant figures are in 820 400.0 L
Answer:
7 significant numbers
Si se usa 450 gramos de carbonato de calcio para dicho proceso ¿Qué volumen de CO2 se obtendrá, si la presión es de 8 atm y la temperatura 200°C? R=0,082 atm.L/mol.K
Respuesta:
21.8 L
Explicación:
Paso 1: Escribir la reacción balanceada
CaCO₃ ⇒ CaO + CO₂
Paso 2: Convertir 450 g de CaCO₃ a moles
La masa molar de CaCO₃ es 100.09 g.
450 g × (1 mol/100.09 g) = 4.50 mol
Paso 3: Calcular los moles de CO₂ que se forman a partir de 4.50 moles de CaCO₃
La relación molar de CaCO₃ a CO₂ es 1:1. Los moles de CO₂ formados son 1/1 × 4.50 mol = 4.50 mol.
Paso 4: Convertir la temperatura a Kelvin
Usaremos la siguiente expresión.
K = °C + 273.15 = 200°C + 273.15 = 473 K
Paso 5: Calcular el volumen de CO₂
Usaremos la ecuación del gas ideal.
P × V = n × R × T
V = n × R × T / P
V = 4.50 mol × (0.082 atm.L/mol.K) × 473 K / 8 atm
V = 21.8 L
What does light travel in?
Answer:
Light travels as a wave.
Explanation:
But unlike sound waves or water waves, it does not need any matter or material to carry its energy along. This means that light can travel through a vacuum—a completely airless space. (Sound, on the other hand, must travel through a solid, a liquid, or a gas.)
