A)ratio of atomic mass of Ca,S,C,O*3=40:32:12:48=10:8:3:12B)ratio of atomic mass of N,H*3=14:3C)ratio of atomic mass of H*2,S,O*4=2:32:64=1:16:32D)ratio of atomic mass of Mg,Cl*2=24:71E)ratio of atomic mass of Ca,O*2, H*2=40:32:2=20:16:1

Ratio of Mass of Combining Elements in Compounds

(A) CASCO3:
- CASCO3 is the chemical formula for calcium carbonate.
- It consists of the elements calcium (Ca), sulfur (S), carbon (C), and oxygen (O).
- To find the ratio of the mass of combining elements, we need to determine the molar mass of each element.
- The molar mass of Ca is 40.08 g/mol, S is 32.06 g/mol, C is 12.01 g/mol, and O is 16.00 g/mol.
- The ratio of the mass of combining elements can be calculated by dividing the molar mass of each element by the smallest molar mass.
- The smallest molar mass in this case is 12.01 g/mol (the molar mass of carbon).
- Therefore, the ratio of mass of combining elements in CASCO3 is:
- Ca: 40.08 g/mol / 12.01 g/mol = 3.34
- S: 32.06 g/mol / 12.01 g/mol = 2.67
- C: 12.01 g/mol / 12.01 g/mol = 1
- O: 16.00 g/mol / 12.01 g/mol = 1.33

(B) NH3:
- NH3 is the chemical formula for ammonia.
- It consists of the elements nitrogen (N) and hydrogen (H).
- The molar mass of N is 14.01 g/mol, and H is 1.01 g/mol.
- The smallest molar mass in this case is 1.01 g/mol (the molar mass of hydrogen).
- Therefore, the ratio of mass of combining elements in NH3 is:
- N: 14.01 g/mol / 1.01 g/mol = 13.87
- H: 1.01 g/mol / 1.01 g/mol = 1

(C) H2SO4:
- H2SO4 is the chemical formula for sulfuric acid.
- It consists of the elements hydrogen (H), sulfur (S), and oxygen (O).
- The molar mass of H is 1.01 g/mol, S is 32.06 g/mol, and O is 16.00 g/mol.
- The smallest molar mass in this case is 1.01 g/mol (the molar mass of hydrogen).
- Therefore, the ratio of mass of combining elements in H2SO4 is:
- H: 1.01 g/mol / 1.01 g/mol = 1
- S: 32.06 g/mol / 1.01 g/mol = 31.75
- O: 16.00 g/mol / 1.01 g/mol = 15.84

(D) MgCl2:
- MgCl2 is the chemical formula for magnesium chloride.
- It consists of the elements magnesium (Mg) and chlorine (Cl).
- The molar mass of Mg is 24.31 g/mol, and Cl is 35.45 g/mol.
- The smallest molar mass in this case is 24.31 g/mol (the molar mass of magnesium).
- Therefore, the ratio of mass of combining elements in MgCl2 is:
- Mg: