Why are there 8 elements in the 3rd stage in a periodic table ?
Answer:
PLEASE MARK ME AS THE BRAINLIEST
Explanation:
According to the 2n2 rule, the maximum number of electrons in the third period = 2 x (3)2 = 18. But, the last shell cannot accommodate more than 8 electrons so, the number of electrons in third period is 8. Hence, the number of elements is also 8.
TIMED PLS PLS HELP ASAP
The scattering of sunlight by the mixture of gas molecules in air results in the blue color of the sky. Calculate the energy (in Joules) of a single photon of blue light with a frequency of 6.00 × 10¹⁴ Hz. (h = 6.626 × 10⁻³⁴ J • s)
Answer:
It's me mario
Explanation:
A sample of gas occupies 1.2 L at 12.0oC. Assuming pressure remains the same, what would be the volume (in L) of this gas at 67oC?
A.
1.4
B.
1.0
C.
0.2
D.
5.0
E.
6.7
Fumaric acid, which occurs in many plants, contains, by mass, 41.4% carbon, 3.47% hydrogen, and 55.1% oxygen. The molecular mass of this compound is 116 amu. The molecular formula of this compound is
Question 15 options:
CHO
C3H3O
C3H3O3
C4H4O4
C6H6O6
Answer:
Explanation:
C = 41.4/12 = 3.43
H = 3.47/1 = 3.47
O = 55.1/16 =3.44
CHO is the skeletal formula (divide each by the lowest number above). The results are close enough to 1 to be 1.
(CHO)_x = 116
C + H + O = 29
(29) _ x = 116
x = 116/29
x = 4
So there area 4 carbons 4 hydrogens and 4 oxygens.
The correct formula is C4H4O4
La masa de una olla es de 300g y contiene 90% de aluminio. Hallar el número de moles de aluminio de la olla. P.A.(Al= 27)
Explanation:
The mass of a pot is 300g and contains 90% aluminum. Find the number of moles of aluminum in the pot. P.A. (Al = 27)
The mass of aluminum present in the pot is:
[tex]300 g * 90/100\\=270 g[/tex]
Hence, in the given pot 270g Al is present.
[tex]Number of moles of Al=\frac{given mass ofAl}{its molar mass}[/tex]
The gram atomic mass of Al -27 g/mol
Given the mass of Al is 270 g
Substitute these values in the above formula:
[tex]Number of moles of Al=\frac{given mass ofAl}{its molar mass}\\=\frac{270 g}{27 g} \\=10.0 mol[/tex]
Answer is 10.0 mol of Al is present.
Which of these is a chemical property of a substance?
Answer:
A chemical property is a characteristic of a substance that may be observed when it participates in a chemical reaction. Examples of chemical properties include flammability, toxicity, chemical stability, and heat of combustion
Liquids have a(n)____shape and A(n)_____volume.
A. indefinite, indefinite
B. indefinite, definite
C. definite, definite
D. definite, indefinite
what is another name for hard water?
Answer:
Hyponym is the another name for hard water.
Explanation:
Please Mark me brainliest
A free-moving neutron is absorbed by the nucleus of an atom. This can
cause:
A. the protons in the nucleus to begin to search for more protons.
B. the atom to become unstable and rip apart.
C. the bonds in the nucleus to become stronger and release heat.
O D. the atom to absorb more neutrons to balance the protons.
Answer:
the atom to become unstable and rip apart.
Explanation:
We define radioactivity as the spontaneous disintegration of atoms. It could occur naturally or artificially.
Artificial radioactivity occurs either by the process of nuclear fusion (combination of two light nuclei) or nuclear fission(bombarding of a heavy nucleus with a small particle such as a neutron).
When a heavy nucleus is bombarded with a neutron, the nucleus becomes unstable and rips apart producing a daughter nucleus/nuclei and more neutrons hence the process continues. This is otherwise called a chain reaction.
!!!!!!URGENT!!!!!!
What do the coefficients in the following balanced chemical equation mean?
2H2 + O2 + 2H2O
A) 2 moles of hydrogen and 1 mole of oxygen in the reactants
B) 2 moles of oxygen and 1 mole of hydrogen in the reactants
C) 2 moles of oxygen and 1 mole of hydrogen in the products
D) 2 moles of hydrogen and 1 mole of oxygen in the products
Answer:
2moles of hydrogen and 1 mole of oxygen in the reactants
What is the name of this compound
Answer:
horizontal
Explanation:
If 45.6 g of CO2 is in a 2.75 L container at 25.0 °C, predict the pressure in this container, in kPa.
Answer:
936.97 KPa
Explanation:
We'll begin by calculating the number of mole in 45.6 g of CO₂. This can be obtained as follow:
Mass of CO₂ = 45.6 g
Molar mass of CO₂ = 12 + (16×2)
= 12 + 32
= 44 g/mole
Mole of CO₂ =?
Mole = mass /molar mass
Mole of CO₂ = 45.6 / 44
Mole of CO₂ = 1.04 mole
Next, we shall convert 25.0 °C to Kelvin temperature. This can be obtained as follow:
T (K) = T (°C) + 273
T (°C) = 25.0 °C
T (K) = 25.0 °C + 273
T (K) = 298 K
Finally, we shall determine the pressure. This can be obtained as follow:
Mole of CO₂ (n) = 1.04 mole
Volume (V) = 2.75 L
Temperature (T) = 298 K
Gas constant = 8.314 KPa.L/Kmol
Pressure (P) =?
PV = nRT
P × 2.75 = 1.04 × 8.314 × 298
P × 2.75 = 2576.67488
Divide both side by 2.75
P = 2576.67488 / 2.75
P = 936.97 KPa
Thus, the pressure is 936.97 KPa
Help please i beg someone answer and explain
Answer:
Q,N,1) lithium + hydrochloric -> lithium chloride + Hydrogen.
word equation ( 2li + 2HCl -> 2liCl + H2)does anyone know the substance of an egg after it has been cooked?
Answer:
Denaturation is what happens when heat is applied to the eggs. ... The heat coming from your stove denatures the protein by disrupting some of its bonds that held the molecule into shape. In the case of hard-boiled eggs, the proteins clump together and solidify, causing the egg white and yolk to harden.
I HOPE THIS WILL HELP YOUHAVE A GREAT DAY :)
If an atom contains more
electrons than protons, it is
Answer:
If an atom has the same number of electrons as protons, it is a neutral atom.
Explanation:
- Write equations for (a) the decomposition of carbon monoxide-
co_to produce carbon--and oxygen gas and (b) the synthesis reaction for the formation of carbon monoxide from carbon and Oxygen.
Explanation:
here's the answer to your question about
name the compound: RuO
[tex]\large \mid \underline {\bf {{{\color{navy}{Ruthenium \: \: oxide...}}}}} \mid[/tex]
A thief who has stolen large quantities of uranium-235 may have increased
the threat of what?
A. Alpha decay
B. Nuclear fusion
C. Nuclear waste
D. Proliferation
Since uranium - 235 decays by alpha decay, the thief runs a risk of exposure to alpha decay.
What is alpha decay?Radioactive decay is the sponteanous disintergration of a nuclide to yiled daughter nuclide and release energy.
We can see the decay of Uranium -235 in the image attached to this answer. Hence, it then follows that the theif here runs the risk of exposure to alpha decay.
Learn more about alpha decay: https://brainly.com/question/9904853
Answer:
D. Prolideration
Explanation:
Just took the test
If 0.8 g of gas Z occupies 0.56 dm at s.1.p., calculate its relative molecular mass. (Molar volume of gas is 22.4 dm.)
Answer:
32
Explanation:
0.56dm of gas has 0.8g
22.4dm of gas Z has a mass of 22.4/0.56X0.8
the relative molecular mass of gas Z is 32
The structure of copper is described as a lattice of positive ions in a 'sea of electrons'.
Which statements are correct?
1 Copper has a high melting point because of the strong electrostatic attraction
between the positive ions and the 'sea of electrons'.
2 Copper is malleable because the layers of atoms in the lattice can slide over each
other.
3 Copper atoms can be oxidised to form copper ions by losing electrons.
A
1, 2 and 3
B
1 and 2 only
с
1 and 3 only
D 2 and 3 only
Answer:
A
Explanation:
Metal atoms are held together by metallic bonds. The metallic bonds are composed of a lattice of positive ions in a 'sea of electrons'.
The metal atoms are held together by strong electrostatic attraction between the positive ions and the 'sea of electrons' leading to high melting point of metals including copper.
Similarly, when a metal undergoes stress, the layers of the metal roll over each other but the lattice remains in place. Hence for metals such as Copper, layers of atoms in the lattice can slide over each other thereby making the metal malleable.
Metals oxidize by electron loss. Since Copper is metal, it can also be oxidized to form copper ions by loosing electrons.
how to convert Kelvin to degree Celsius? is there any method
Answer:
[tex]{ \tt{kelvin = 273 + celcius \: degree}} \\ { \boxed{ \bf{celcius = kelvin - 273}}}[/tex]
Answer:
To convert Kelvins into Celsius degrees, the formula is K − 273.15 = °C
Pls mark me brainliest.
What is the product of the unbalanced equation below?
Al(s) + Br2(g) →
The Periodic Table
O A. Al(s) + Br2(g)
B. AlBr(s)
C. Al2Br3(s)
O D. AlBr3(s)
Answer:
D
Explanation:
The answer is D. I'm not sure that it is a solid. I don't think it is a ppte, which is the only way it can be a true solid. It is ionic if the reaction is taking place in water and there is someway to start the reaction. Be that as it may, the internal balace numbers of the chemical produced is the only possible answer. The balanced eq;uatioon is
2Al + 3Br2 ==> 2AlBr3
what is 2n2 formula?
Answer:The distribution of electrons in an atom is called as Electronic Configuration. Formula 2n2 helps in the determination of the maximum number of electrons present in an orbit, here n= orbit number.
Explanation:
In an experiment, a student wants to increase the rate of a reaction that involves gases. Which change to the
reactants would accomplish this?
Increase the volume to decrease pressure and to increase concentration.
O Increase the volume to increase pressure and to decrease concentration.
O Decrease the volume to decrease pressure and to increase concentration.
O Decrease the volume to increase pressure and to increase concentration.
Answer:
Decrease the volume to increase pressure and to increase concentration.
Explanation:
Increasing the concentration will increase the number of collisions per second and therefore the rate of reaction.
Pls mark me as brainliest.
Answer:
The last option: Decrease the volume to increase pressure and to increase concentration.
Explanation:
You can support your choice on basis of the collision theory. According to the collision theory, chemical reactions happen when the molecules collide with each other, in the correct orientation and with enough kinetic energy to overcome the activation energy. As a consequence, the larger the number of collisions the larger the rate of a reaction. In the case of a reaction that involves gases, decreasing the volume will increase the pressure and the concentration (volume is inversely related to both the pressure and the concentration) causing the molecules to be closer to each other and to collide with higher frequency, this is you will expect more collisions, and so an increase on the rate of the reaction. That is expressed by the last choice: decrease the volume to increase pressure and to increase concentration.
The diagram shows three isotopes. What element is represented?
hydrogen
helium
lithium
Answer:
The diagram shows three isotopes. What element is represented?
A. hydrogen
B. helium
C. lithium
A. hydrogen
A. Is The Correct Answer
Which is a mixture?
Sodium metal
chlonne gas
sodium metal and chlonne gas
sodium chlonde (salt) and water
Answer:
I believe it's salt and water
Explanation:
not sure
Answer:
Mixture is a electronic device used to peel the things such as onion ,tomato,ginger, garlic etc.
Which statements describe lattice energy?
Answer:
It increases as the size of the ions decreases.
It increases as the charge on the ions increases.
It is a measure of the strength of the bonds between ions in a compound.
Explanation:
Hope this helps ♡
I need help answering this question in relation to Stoichiometry volume-mass in my chemistry class.
oha ya çok ilginç nerdeyim ben ab
______ exhibits the highest
intermolecular forces of the states of matter.
A. Solid
B. Liquid
C. Gas
D. Vacuum

Solve these.. . . . .
Answer:
Please find the ten balanced equations below
Explanation:
According to the question, a balanced equation must contain equal number of atoms on both sides of the equation. To balance an equation, coefficients are used. The following are the balanced equation:
1. C + O2 → CO2 (balanced)
2. 2H2 + O2 → 2H2O (balanced)
3. 2Na + 2H2O → 2NaOH + H2 (balanced)
4. 4Na + O2 → 2Na2O (balanced)
5. 2Na + Cl2 → 2NaCl (balanced)
6. NaOH + HCl → NaCl + H2O (balanced)
7. NaOH + HNO3 → NaNO3 + H2O (balanced)
8. 2NaOH + H2SO4 → Na2SO4 + 2H2O (balanced)
9. Na2CO3 + 2HCl → 2NaCl + H2O + CO2 (balanced)
10. 2NaOH + CO2 → Na2CO3 + H2O (balanced)
