Answer:
141g of CCl₄
Explanation:
First, we have to write the balanced equation.
CCl₄(g) + 2 HF(g) ⇄ CF₂Cl₂(g) + 2 HCl(g)
We can calculate how many moles of CF₂Cl₂ using the ideal gas equation.
V = 14.9 dm³ = 14.9 L
T = 21°C + 273.15 = 294.15 K
P = 1.48 atm
R = 0.08206 atm.L/mol.K
We can use proportions to find the mass of CCl₄ required to obtain 0.914 moles of CF₂Cl₂. According to the balanced equation, 1 mol of CF₂Cl₂ is produced when 1 mol of CCl₄ reacts. And the molar mass of CCl₄ is 154 g/mol.
The correct answer is 96.80 grams
Explanation:
The density of a substance shows the total mass the substance contains in 1 mL or 1 cm3 as density is calculated by using the formula D= M (mass) / V (volume). This implies, Iron contains 7.87 grams per milliliter. Moreover, this value and formula can be used to calculate the mass or volume of any other sample. The process to calculate the mass of an iron sample with a volume of 12.3 mL is shown below.
D = M ÷ V
7.87 mL = x ÷ 12.3 mL - x represents the missing value. Now find the value of x by solving the equation
x = 7.87 · 12.3
x = 96.80
This means a sample of 12.3 mL contains a mass of 96.80 grams. Also, you can know this value is correct because if you divide the mass by the value the density is the same (96.80 grams ÷ 12.3 mL = 7.87 g/mL)
When scientists say that a theory can never be proven it is always possible for a new data to contradict a theory
