Advertisements
Advertisements
Question
Calculate the formula unit mass of K2CO3 given the atomic mass of
- Zn = 65 u
- Na = 23 u
- K = 39 u
- C = 12 u
- O = 16 u
Advertisements
Solution
Formula unit mass of K2CO3 = 2 × Atomic mass of K + Atomic mass of C + 3 × Atomic mass of O
= 2 × 39 + 12 + 3 × 16
= (78 + 12 + 48)u
= 138 u
APPEARS IN
RELATED QUESTIONS
Define 'molecular mass' of a substance.
Calculate the molecular mass of hydrogen bromide (HBr). (Atomic masses : H = 1 u ; Br = 80 u)
Calculate the molecular masses of the following :
Ammonia, NH3
(Atomic masses : H = 1 u ; O = 16 u ; Cl = 35.5 u ; N = 14 u ; C = 12 u)
What is meant by the ‘molar mass’ of a substance ? State the unit in which molar mass is usually expressed.
Calculate the molecular mass of the following:
Mg3N2
Given atomic mass of Cu = 63·5, H = 1, O = 16, C = 12, N = 14, Mg = 24, S = 32
An unknown gas shows a density of 3 g per litre at 273°C and 1140 mm Hg pressure. What is the gram molecular mass of this gas?
Calcium carbonate is decomposed on heating in the following reaction
CaCO3 → CaO + CO2
How many moles of CO2 are there in this equation?
The mass of one steel screw is 4.11g. Find the mass of one mole of these steel screws. Compare this value with the mass of the Earth (5.98 × 1024kg). Which one of the two is heavier and by how many times?
The modem atomic mass scale is based on ______.
Write the name of the following compound and deduce its molecular mass.
NaOH
