Answer:
334.2× 10²³ molecules
Explanation:
Given data:
Mass of water = 1 Kg ( 1000 g )
Number of molecules = ?
Solution:
Number of moles of water:
Number of moles = mass/ molar mass
Number of moles = 1000 g/ 18 g/mol
Number of moles = 55.5 mol
1 mole contain 6.022× 10²³ molecules
55.5 mol×6.022× 10²³ molecules
334.2× 10²³ molecules
Given:
Mass, m = 51.1 g
Volume, V = 6.63 cm³
By definition,
Density = Mass/Volume
= (51.1 g)/(6.63 cm³)
= 7.7074 g/cm³
In SI units,
Density = (7.7074 g/cm³)*(10⁻³ kg/g)*(10² cm/m)³
= 7707.4 kg/m³
Answer: 7.707 g/cm³ or 7707.4 kg/m³