For the very last question you would first divide 8,900 by 12 and the number you get will be the answer. You should get 741.66
Answer:
5 mg
Explanation:
If one half life is 4 hours, then 3 half lives is 12 hours.
This means that the sample will decay to 1/8 of its original amount.
So, the answer is 40(1/8) = 5 mg.
Answer:
392g sulfuric acid are produced
Explanation:
Based on the balanced equation:
2HCl + Na2SO4 → 2NaCl + H2SO4
<em>2 moles of HCl produce 1 mole of sulfuric acid</em>
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To solve the problem we need to find the moles of sulfuric acid produced based on the chemical equation. Then, using its molar mass -<em>Molar mass H2SO4 = 98g/mol- </em>we can find the mass of sulfuric acid produced:
<em>Moles sulfuric acid:</em>
8mol HCl * (1mol H2SO4 / 2mol HCl) = 4 mol H2SO4
<em>Mass sulfuric acid:</em>
4mol H2SO4 * (98g / mol) =
392g sulfuric acid are produced
Answer:
1.78 × 10²⁶ Atoms
Explanation:
Relation between number of molecules and moles is,
No. of Molecules = Moles × 6.022 × 10²³ Molecules/mol
No. of Molecules = 99 mol × 6.022 × 10²³ Molecules/mol
No. of Molecules = 5.96 × 10²⁵ Molecules
Also, In CO₂ Molecule there are 3 atoms.
So,
No. of atoms = 5.96 × 10²⁵ Molecules × 3
No. of atoms = 1.78 × 10²⁶ Atoms
