How many grams of KCl are needed to prepare 0.5 moles of KCl?
Practice Questions
1 question
Q1
How many grams of KCl are needed to prepare 0.5 moles of KCl?
37.5 g
45 g
50 g
60 g
The molar mass of KCl is approximately 74.5 g/mol. Therefore, 0.5 moles of KCl will weigh 0.5 x 74.5 g = 37.25 g.
Questions & Step-by-step Solutions
1 item
Q
Q: How many grams of KCl are needed to prepare 0.5 moles of KCl?
Solution: The molar mass of KCl is approximately 74.5 g/mol. Therefore, 0.5 moles of KCl will weigh 0.5 x 74.5 g = 37.25 g.
Steps: 6
Step 1: Find the molar mass of KCl. KCl is made of potassium (K) and chlorine (Cl). The atomic mass of K is approximately 39.1 g/mol and Cl is approximately 35.5 g/mol.
Step 2: Add the atomic masses together to get the molar mass of KCl. So, 39.1 g/mol + 35.5 g/mol = 74.6 g/mol (rounded to 74.5 g/mol).
Step 3: Determine how many moles of KCl you want to prepare. In this case, it is 0.5 moles.
Step 4: Use the formula: mass (in grams) = number of moles x molar mass. Here, it will be 0.5 moles x 74.5 g/mol.
Step 5: Calculate the mass. 0.5 x 74.5 = 37.25 grams.
Step 6: Conclude that you need 37.25 grams of KCl to prepare 0.5 moles.
