Answer:
A) Sample B has more calcium carbonate molecules
Explanation:
M = Molar mass of calcium carbonate = 100.0869 g/mol
= Avogadro's number = 
For the 4.12 g sample
Moles of a substance is given by

Number of molecules is given by

For the 19.37 g sample

Number of molecules is given by


So, sample B has more calcium carbonate molecules.
The ratio of the elements of carbon, oxygen, calcium atoms, ions, has to be same in both the samples otherwise the samples cannot be considered as calcium carbonate. Same is applicable for impurities. If there are impurites then the sample cannot be considered as calcium carbonate.
Answer:
5.231 L.
Explanation:
- Molarity is the no. of moles of solute per 1.0 L of the solution.
<em>M = (no. of moles of KCl)/(Volume of the solution (L))</em>
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M = 6.5 M.
no. of moles of solute = 34.0 mol,
Volume of the solution = ??? L.
∴ (6.5 M) = (34.0 mol)/(Volume of the solution (L))
∴ (Volume of the solution (L) = (34.0 mol)/(6.5 M) = 5.231 L.
(C) Electron cloud
the electron cloud is formed by all the electrons in the atom
The formula for the compounds in the reaction are as follows with the respective states
Carbon monoxide - CO (g)
hydrogen - H₂ (g)
methane - CH₄(g)
water - H₂O (l)
reaction of carbon monoxide with hydrogen gas gives rise to methane and water
the balanced chemical equation for the above reaction is as follows
CO(g) + 3H₂(g) --> CH₄(g) + H₂O(l)
Butane is C₄H₁₀.

The balanced equation is 2 C₄H₁₀ + 13 O₂ <span>→</span> 8 CO₂ + 10 H₂O.