A cube has a mass of 42 grams and a volume of 15 cubic centimeters. What is it’s density? (Show your work or complete all problems for brainliest)

2.8g/cm³

Explanation:

Given parameters:

Mass of cube = 42g

Volume of cube  = 15cm³

Unknown:

Density of the cube  = ?

Solution:

Density is defined as the mass per unit volume of a substance. It is mathematically expressed as:

 Density  =  

So;

 Density  =   = 2.8g/cm³

Molar mass of the unknown gas is 8.96g/mol

Explanation:

Hello,

According to Graham's law of diffusion, its states that the rate of diffusion of a gas is inversely proportional to the square root of its molecular mass

R = k (1/√(M))

R = rate of diffusion

M = molecular mass

R₁ / R₂ = √(M₂ / M₁)

R₁ = nitrogen = 68.3s

R₂ = unknown gas = 85.6s

M₂ = molecular mass of the unknown gas

M₁ = molecular mass of nitrogen = 14g/mol

68.3 / 85.6 = (√M₂ / 14)

0.8 = (√M₂ / 14)

Take square of both sides

0.8² = M₂ / 14

M₂ = 14 × 0.64

M₂ = 8.96g/mol

The molar mass of the unknown gas is 8.96g/mol