Answer:
here hope it helps
Explanation:
covalent bonds
How or why does lead affect bones and teeth?
Answer:
Lead can harm production of blood cells and the absorption of calcium needed for strong bones and teeth, muscle movements, and the work of nerves and blood vessels. High lead levels can cause brain and kidney damage.
thanks
Once lead enters the body, it is distributed to organs such as the brain, kidneys, liver and bones. The body stores lead in the teeth and bones where it accumulates over time. Lead stored in bone may be remobilized into the blood during pregnancy, thus exposing the fetus.
A chemist mixed two substances together: a blue powder with no smell and a colorless liquid with a strong smell. Their repeating groups of atoms are shown below on the left. After they were mixed, the chemist analyzed the results and found two substances. One ending substance had the repeating group of atoms shown below on the right. Is the ending substance the same substance as the blue powder? What happened to the atoms of the starting substances when the ending substances formed
Answer:
Vanished completely.
Explanation:
The atoms of starting substances are transformed into the ending substances because the starting substances mixed with each other and turn into new substances. The starting substances i.e. reactants vanished completely when the ending substances means products are formed completely so we can say that the vanishing of ending substance happened when the ending substances are formed.
A curium-245 nucleus is hit with a neutron and changes as shown by the equation. Complete the equation by filling in the missing parts. 52 54 138 140 142 Xe Te Ce
The question is incomplete, the complete question is:
A curium-245 nucleus is hit with a neutron and changes as shown by the equation. Complete the equation by filling in the missing parts.
[tex]_{96}^{245}\textrm{Cm}+_0^1\textrm{n}\rightarrow _{42}^{103}\textrm{Mo}+_{r}^{q}\textrm{p}+3_0^1\textrm{n}[/tex]
Answer: The complete equation formed is [tex]_{96}^{245}\textrm{Cm}+_0^1\textrm{n}\rightarrow _{42}^{103}\textrm{Mo}+_{54}^{140}\textrm{Xe}+3_0^1\textrm{n}[/tex]
Explanation:
The general representation of an isotope is given as:
[rex]_Z^A\textrm{X}[/tex]
where,
A is the mass number, Z is the atomic number and X is the symbol of the element
In a nuclear reaction, total atomic number and total mass number on either side of the reaction remains the same
For the given chemical reaction:
[tex]_{96}^{245}\textrm{Cm}+_0^1\textrm{n}\rightarrow _{42}^{103}\textrm{Mo}+_{r}^{q}\textrm{p}+3_0^1\textrm{n}[/tex]
On the reactant side:
Total atomic number = [96 + 0] = 96
Total mass number = [245 + 1] = 246
On the product side:
Total atomic number = [42 + r + 0] = 42 + r
Total mass number = [103 + q + 3] = 106 + q
Calculating for 'r' and 'q', we get:
[tex]96= 42 + r\\\\r=96-42=54[/tex]
[tex]246 = 106+q\\\\q=246-106=140[/tex]
Thus, the missing isotope is [tex]_{54}^{140}\textrm{Xe}[/tex]
Hence, the complete equation formed is [tex]_{96}^{245}\textrm{Cm}+_0^1\textrm{n}\rightarrow _{42}^{103}\textrm{Mo}+_{54}^{140}\textrm{Xe}+3_0^1\textrm{n}[/tex]
Answer: try 140 52 xe
Explanation:
Is soup pure or impure?
Answer:
I think it's impure . Hope this helps you
Answer:
I think is pure but not 100% pure.
2. Which element below would be the best choice when creating a covalent molecule with an
Oxygen atom?
A. Na
B. Mg
C. Ne
D. O
helo in this please I'm so kunfused
OPTION C is the correct answer.
Calculate how many methane molecules and how many carbon and hydrogen atoms are there in 25 g of Methane?
From the formula of methane it is clear that one mole of methane has 4hydrogen atoms. So, 37.6×1023 hydrogen atoms are there in 25.0 g of methane. Therefore, 9.4×1023methane molecules and 9.4×1023 hydrogen and 37.6×1023carbon atoms are there in 25.0 g of methane.
mark me brainliestt :))
Which of these is true for natural selection but not artificial selection?
A.Humans choose specific organisms to reproduce.
B.Competition for resources determines reproductive success.
C.Unfavorable traits decrease in frequency in a population.
D.Genetic engineering introduces new traits into a population.
Answer:
B
Explanation:
The formula for calclum chloride Is CaCl2. Which argument best describes the type of chemical bond that was formed between the calcium and chlorine atoms? An lonic bond because calcium is sharing its electrons with the chlorine. A covalent bond because calclum is transferring its electrons to the chlorine. A covalent bond because calcium is sharing its electrons with the chlorine. An lonic bond because calcium is transferring Its electrons to the chlorine.
Answer:
An lonic bond because calcium is transferring Its electrons to the chlorine.
Explanation:
Metals usually form compounds with non-metals through ionic bonding.
Metals are electropositive elements which form ions by the loss of electrons, whereas non-metals are electronegative elements which form ions by the gain of electrons.
Compounds are formed when two or more elements combine together. The formation of compounds involves formation of bonds which may be either ionic or covalent bonds.
The type of bonding that exists between the a metallic calcium atoms and non-metallic chlorine atoms in calcium chloride, CaCl₂, is ionic bonding. In the process of formation of the compound, calcium atoms which have a valency of 2 readily donates their two valence electrons to chlorine atoms to form calcium ions, Ca²+. Each chlorine atoms having a valency of 1 accepts an electron to form chloride ions Cl-. Two chlorine atoms accept the two electrons donated by a calcium ion. Due to strong electrostatic forces of attraction between the calcium ion and the two chloride ions, the ionic compound CaCl₂ is formed.
Question: (02.01 MC) Which state of matter does this image represent?
O Solid
O Liquid
O Gas
O Plasma
Please answer. Brainliest!
The equation is balanced.
Explanation:The number of P atoms in the reactant side is 4 and the number of P atoms in the product side is also 4.
The number of O atoms in the reactant side is 16 and the number of O atoms in the product side is also 16.
The number of H atoms in the reactant side is 12 and the number of H atoms in the product side is also 12.
These results are in accordance with the law of conservation of mass.
#ILoveChemistry
The reaction of hydrogen with nitrogen to produce ammonia is shown below. If there are 3 moles of nitrogen, how many moles of hydrogen are needed to react completely with the nitrogen?
Answer:
9
Explanation:
I took the same test :)
The stoichiometry is important in chemistry which helps us to use the balanced equation to calculate the amount of reactants and products. Here the moles of hydrogen needed is 9. The correct option is B.
What is stoichiometry?The quantitative study of the reactants and products involved in a chemical reaction is known as the chemical stoichiometry. The stoichiometric coefficients can be fractions including the whole numbers. It helps to establish the mole ratio.
The stoichiometric coefficient is basically the number which is present in front of the atoms, molecules or ions. The stoichiometric calculations are also used in gravimetry and volumetry.
Here the balanced equation for the reaction is:
N₂ + 3H₂ → 2NH₃
Number of moles of H₂ = 3 mol N₂× 3 mol H₂ / 1 mol N₂ = 9 mol H₂
So the number of moles of H₂ is 9.
Thus the correct option is B.
To know more about stoichiometry, visit;
https://brainly.com/question/29775083
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The solubility of gases in liquids The solubility of gases in liquids increases as temperature increases and increases as pressure increases. increases as temperature increases and decreases as pressure increases. decreases as temperature increases and decreases as pressure increases. decreases as temperature increases and increases as pressure increases. is independent of temperature and increases as pressure increases.
Answer:
As the kinetic energy of the gaseous solute increases, its molecules have a greater tendency to escape the attraction of the solvent molecules and return to the gas phase. Therefore, the solubility of a gas decreases as the temperature increases.
Explanation:
As the kinetic energy of the gaseous solute increases, its molecules have a greater tendency to escape the attraction of the solvent molecules and return to the gas phase. Therefore, the solubility of a gas decreases as the temperature increases
An inverse relationship can be represented by what?
Answer:
1/....
Explanation:
If we say acceleration 'a' is inversely proportional to mass 'm', then
a=1/m.
Which process, in order, would be necessary for this sequence of the rock cycle:
rock → metamorphic rock → igneous rock
Heat and pressure → melting → cooling
Weathering and erosion → compaction → weathering and erosion
Melting → cooling → melting → erosion
Cooling → melting → cooling → weathering and erosion
Answer:
may be the answer is Heat and pressure - melting - cooling
How many moles are in 2.11 x 1014 molecules of LiBr?
Answer: There are [tex]12.71 \times 10^{-9}[/tex] moles present in [tex]2.11 \times 10^{14}[/tex] molecules of LiBr.
Explanation:
According to the mole concept, there are [tex]6.022 \times 10^{23}[/tex] molecules present in 1 mole of a substance.
Hence, moles in [tex]2.11 \times 10^{14}[/tex] molecules of LiBr are calculated as follows.
[tex]Moles = \frac{2.11 \times 10^{14}}{6.022 \times 10^{23}}\\= 12.71 \times 10^{-9}[/tex]
Thus, we can conclude that there are [tex]12.71 \times 10^{-9}[/tex] moles present in [tex]2.11 \times 10^{14}[/tex] molecules of LiBr.
What makes plants the beginning of the food chain?
please answer my question aswell as my last one!
Answer: A
Explanation:
i just took the quiz and it was right!
what is the digiMelt Start Temp and the digiMelt Stop Temp for Formic Acid Acetic Acid Propionic Acid
Explanation:
Melting is defined as the physical process where a solid state of a substance converts into its liquid state. No change of chemical composition takes place, just the physical state of water is changing.
[tex]\text{Solid}\rightleftharpoons \text{Liquid}[/tex]
There are given carboxylic acids. The melting point of these acids increases to its second group member which is ethanoic acid due to prevalent hydrogen bonding. To break this bonding, a high amount of heat needs to be applied.
But as we move forward, the melting point decreases sharply as an increase in the number of carbon atoms decreases the hydrogen bonding.
Melting point of Formic Acid = [tex]8.3^oC[/tex]
Melting point of Acetic Acid = [tex]16.6^oC[/tex]
Melting point of Propionic Acid = [tex]-21^oC[/tex]
Why increasing the temperature of a gas would increase the volume of its container in gas law?
When the amount of gas in a container is increased, the volume increases. Lussac's law states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature.
Additional Activities
Direction: Sharpen your understanding in projectile motion. Calculate the maximum height reached and the horizontal range of the given launched angles and initial velocity of a projectile. You may opt to use the Projectile Motion Simulation with Air Friction by AERDEMIR which can be downloaded via Play Store for free.
1. To use the simulator, set the given values as shown in the left.
Start Angle = Launched Angle = refer to the table Start Velocity = Initial Velocity = 20 m/s
Change the gravitational acceleration to 9.8 only Delete the values in Air Density and Drag Coefficient
2. Deactivate the friction force by tapping the icon indicated in the above image.
The maximum height of an object, given the initial launch angle and initial velocity is found with:
h = v2 is in2θi 2g
h = v i 2 sin 2 θ i 2 g.
The radius of the large cylinder of a hydrolic press
20cm and that of the small cylinderis 5 cm. If a force of 100N is applied on the small piston Calculate the force on the large piston. if the piston of the small cylinder move through a distance of 0.4m through what distance can the large piston be raised
Answer: 1) 400N
2)1.6
Explanation:
1) 5cm = 100N of force
so
20cm=400n
2) 0.4 X 4 = 1.6
Pure hydrogen (H₂) is a hazardous substance. Thus, safer and more cost effective techniques have been developed to store it as a solid for shipping purposes. One such method is the reaction below, which occurs at 200 °C.
Answer: hello your question has some missing details attached below is the missing details
answer : 25.5% ( B )
Explanation:
Determine percentage yield
molar mass = 35 g/mol
mass of Li₃N(s) = 70 g
product LiH(s) = 8.0 g ( actual yield )
theoretical yield ( LiH ) = 4 * 7.95 = 31.8 g
percentage yield = actual yield * 100 / theoretical yield
= 8 * 100/31.8
= 25.5%
A certain atom has a mass of 16 and an atomic number of 7. What element is this ?
Answer:
Nitrogen
Explanation:
According to the Periodic Table, the atom with a mass is 16 but the Atomic number is 7 for Nitrogen. That means that Nitrogen is an isotope.
Which of these takes place when a chemical change occurs? option 1: Bonds connecting atoms in products and reactants form. option 2: Bonds connecting atoms in products and reactants break. option 3: Bonds connecting atoms in reactants break, and bonds connecting atoms in products form. option 4: Bonds connecting atoms in reactants form, and bonds connecting atoms in products break.
Answer: Out of the given options bonds connecting atoms in reactants break, and bonds connecting atoms in products form are the changes which takes place when a chemical change occurs.
Explanation:
A change that leads to the change in chemical composition of a substance is called a chemical change.
For example, [tex]2NH_{3} \rightarrow N_{2} + 3H_{2}[/tex]
Here, bond between the reactant atoms nitrogen and hydrogen is broken down.
On the other hand, bond connecting the products that is [tex]N_{2}[/tex] and [tex]H_{2}[/tex] is formed.
Thus,, we can conclude that out of the given options bonds connecting atoms in reactants break, and bonds connecting atoms in products form are the changes which takes place when a chemical change occurs.
Please help! I don't know how to do and want to understand
A student is provided with a sample of iron pyrite and a sample of gold. Suggest how the student could distinguish between the two substances
Answer:
Gold and pyrite both have a brilliant metallic luster, but are different tones of yellow. Gold is golden to silvery yellow, whereas pyrite is a pale to medium brassy yellow that sometimes tarnishes.
Explanation:
How many milliliters of 5.0 M NaOH are needed to exactly neutralize 40. milliliters of 2.0 M HCl?
Answer:
16mL
Explanation:
Using the following formula;
CaVa = CbVb
Where;
Where
Ca = concentration/molarity of acid (M)
Va = volume of acid (mL)
Cb = concentration/molarity of base (M)
Vb = volume of base (mL)
According to the information provided in this question;
Ca (HCl) = 2M
Cb (NaOH) = 5M
Va (HCl) = 40mL
Vb (NaOH) = ?
Using CaVa = CbVb
Vb = CaVa/Cb
Vb = 2 × 40/5
Vb = 80/5
Vb = 16mL
The skin has and needs natural oils. Why is it advisable
to wear gloves while working with strong alkalis ?
Answer:
As we know that alkalis react with oil to form soap. As our skin contains oil so when we touch strong alkalis, a reaction takes place and the soapy solution is formed. Hence we should wear gloves.
Answer:
As we know that alkalis react with oil to form soap. As our skin contains oil so when we touch strong alkalis, a reaction takes place and the soapy solution is formed. Hence we should wear gloves.
Explanation:
it from internet
Explain why the buffering action of these chemical reactions is limited by the present day rate of change for atmospheric CO2 concentration
Answer:
Due to increase in carbondioxide gas.
Explanation:
The buffering action of these chemical reactions is limited by the present day rate of change for atmospheric carbondioxide concentration because the the rate of atmospheric carbondioxide rises as compared to ancient atmospheric carbondioxide gas. Due to increase of human activities, the concentration of carbondioxide gas increases in the atmosphere which limits the buffering action of these chemical reactions so we can say that carbondioxide gas is responsible for its limited action.
Suppose that you want to make 12 g of lithium oxide.
What are the minimum masses of lithium and oxygen you will need?
A. Li= 5.6 g O2= 6.4 g
B. Li 6.5 g O2= 4.6 g
C. Li= 0.6 g O2 46.4 g
D. Li= 15.6 g O2 6.4 g
Answer:
A. Li= 5.6 g O2= 6.4 g
Explanation:
Lithium oxide, Li2O, is an oxide that contains 2 moles of Li and 1 mole of O per mole of oxide. To solve this question we must find the mass of each atom in the molecule as follows:
2Li = 2*6.941g/mol = 13.882g/mol
O = 1*16g/mol = 16g/mol
Molar mass Li2O:
16+13.882 = 29.882g/mol
The mass of lithium is:
12g * (13.882g/mol / 29.882g/mol) = 5.6g Li
And the mass of oxygen:
12g * (16g/mol / 29.882g/mol) = 6.4g O
Right answer is:
A. Li= 5.6 g O2= 6.4 g