Question

classmate
Date
Page
Section C
a) Write the formulae for the following and calculate the molecular mass
✓ for each one of them. ( atomic no hydrogen is 1u nitrogen 14u oxygen 16u helium 4u)
i. Water
ii. Nitric acid
b) Calculate the number of moles in 8 grams of Helium?
c) Define Avagadro Number​

Answer 1

Explanation:

water - H2O mass (1*2+16) = 18 amu

nitric acid - HNO3 mass (1+14+16*3) = 63 amu

no. of moles = given weight/most weight.

=8/4 =2 moles

c)

Avogadro's number, number of units in one mole of any substance (defined as its molecular weight in grams), equal to 6.02214076 × 1023. The units may be electrons, atoms, ions, or molecules