Question

3. Given the following equation:

2 K+ Cl2 --->2 KCI
How many grams of KCl are produced from 2.50 g of K and excess Cl2?

show work.

Answer 1

From 2.50 g of K and excess Cl2, 4.77 grams of KCl are produced. This is calculated using stoichiometry, where the given mass of K is converted to moles, ratio of moles from the balanced equation is applied, and finally converted back to grams of KCl using its molar mass.

Step-by-step explanation:

To calculate the number of grams of KCl produced from 2.50 g of K when reacted with excess Cl2, we'll follow these steps:

Write the balanced chemical equation: 2 K + Cl2 → 2 KCl.

Calculate the molar mass of K (potassium), which is approximately 39.10 g/mol.

Determine how many moles of K are present in 2.50 g of K using the formula: moles = mass (g) / molar mass (g/mol). This gives 2.50 g / 39.10 g/mol = 0.064 moles of K.

According to the stoichiometry of the balanced equation, 1 mole of K produces 1 mole of KCl. Therefore, 0.064 moles of K will produce 0.064 moles of KCl.

Calculate the molar mass of KCl, which is approximately 74.55 g/mol.

Multiply the moles of KCl by its molar mass to find the mass of KCl produced: 0.064 moles × 74.55 g/mol = 4.77 g of KCl.

Therefore, 4.77 grams of KCl are produced from 2.50 grams of K and excess Cl2.

Answer 2

4.767 grams of KCl are produced from 2.50 g of K and excess Cl2

Step-by-step explanation:

The balanced equation is

2 K+ Cl2 --->2 KCI

Here the limiting agent is K. Hence, the amount of KCl will be calculated as per the mass of 2.50 gram of K

Mass of one atom/mole of potassium is 39.098 grams

Number of moles is 2.5 grams =
`(2.5)/(39.098) = 0.064`

So, 2 moles of K produces 2 moles of KCL

0.064 moles of K will produces 0.064 moles of KCl

Mass of one molecule of KCl is 74.5513 g/mol

Mass of 0.064 moles of KCl is 4.767 grams