Question

question 5 6 pts how many o atoms are present in 1.04 mol of mgso4? 1.04×10^23 atoms 4.16×10^23 atoms 6.26×10^23 atoms 2.51×10^24 atoms question 6 6 pts how many moles are present in a sample of hcl with a mass of 3.65 g? 0.100 mol 3.46 mol 2.19×10^24 mol 10.0 mol

Explanation:

Question 5

Step1: Determine O atoms per molecule

In one molecule of $MgSO_4$, there are 4 O atoms.

Step2: Calculate moles of O atoms

Given 1.04 mol of $MgSO_4$, moles of O atoms = $1.04\times4 = 4.16$ mol.

Step3: Use Avogadro's number

Avogadro's number $N_A=6.022\times 10^{23}$ atoms/mol. Number of O atoms = $4.16\times6.022\times 10^{23}\approx 2.51\times 10^{24}$ atoms.

Step1: Find molar mass of HCl

The molar mass of H is approximately 1 g/mol and Cl is approximately 35.5 g/mol. So molar mass of HCl, $M = 1 + 35.5=36.5$ g/mol.

Step2: Calculate moles

Using the formula $n=\frac{m}{M}$, where $m = 3.65$ g and $M = 36.5$ g/mol. Then $n=\frac{3.65}{36.5}=0.100$ mol.

Answer:

$2.51\times 10^{24}$ atoms

Question 6