Question

read the ck - 12 lesson below (also watching the videos inserted), then answer the following questions. 10.4 conversions between moles and mass 1.) 1 mole of an ionic compound is equal to the (1 point) formula mass in grams molecular mass atomic number none of the above 2.) what is the mass in grams of 0.40 moles of sodium borohydride, nabh₄? your answer should be rounded to the nearest whole number. (1 point) 15 g 14 g 02 g 38 g

Explanation:

Step1: Recall mole - mass relationship for ionic compounds

For ionic compounds, 1 mole is equal to the formula mass in grams. Molecular mass is for covalent compounds, atomic number is the number of protons in an atom, so the answer to the first question is based on this definition.

Step2: Calculate molar mass of $NaBH_4$

The molar mass of $Na$ (sodium) is approximately $23\ g/mol$, $B$ (boron) is approximately $11\ g/mol$, and $H$ (hydrogen) is approximately $1\ g/mol$. For $NaBH_4$, the molar mass $M = 23+11 + 4\times1=38\ g/mol$.

Step3: Calculate mass from moles

Use the formula $m = n\times M$, where $n = 0.40\ mol$ and $M = 38\ g/mol$. So $m=0.40\times38 = 15.2\ g$. Rounding to the nearest whole - number gives $15\ g$.

Answer:

1. Formula mass in grams
2. 15 g