a 250 g sample is composed of 150 g of sodium...

a 250 g sample is composed of 150 g of sodium (na) and 100 g of chlorine (cl). what is the percent by mass of cl in the sample? 50% 70% 60% 40%

Answer

# Explanation: ## Step1: Recall the formula for mass - percent The formula for mass - percent of a component in a sample is \(\text{Mass}\%=\frac{\text{Mass of component}}{\text{Mass of sample}}\times100\%\) ## Step2: Identify the values The mass of \(Cl\) (component) \(m = 100\space g\), and the mass of the sample \(M=250\space g\) ## Step3: Substitute the values into the formula \(\text{Mass}\%=\frac{100}{250}\times 100\%=\frac{100\times100\%}{250}\) \[ \begin{align*} \frac{100\times100\%}{250}&=\frac{10000\%}{250}\\ & = 40\% \end{align*} \] # Answer: \(40\%\) (the fourth option)