The mass of NaCl formed is 8.307 grams
<u><em> calculation</em></u>
step 1: write the equation for reaction
Na₂CO₃ + 2HCl → 2 NaCl +CO₂ +H₂O
Step 2: find the moles of Na₂CO₃
moles = mass/molar mass
The molar mass of Na₂CO₃ is = (23 x2) + 12 + ( 16 x3) = 106 g/mol
moles = 7.5 g/106 g/mol =0.071 moles
Step 3: use the mole ratio to determine the mole of NaCl
Na₂CO₃:NaCl is 1:2 therefore the moles of NaCl =0.07 x2 =0.142 moles
Step 4: calculate mass of NaCl
mass= moles x molar mass
the molar mass of NaCl= 23 +35.5 =58.5 g/mol
mass = 0.142 moles x 58.5 g/mol =8.307 grams
<h2><em>Al2 S3</em></h2>
<em><u>The formula for aluminum sulfide is Al2 S3.</u></em>
<h2><em>hope it helps</em><em>!</em></h2>
Here first we will identify the number of significant figures in the given two dimensions
2.3mm : there are two significant numbers
8.00mm: there are three significant numbers
so we will report the answer to minimum number of significant number , which is two
the answer is 18.4
We will report it to be 18 mm^2