Answer:
7.5 gm left
Explanation:
Bismuth-210 has a half life of 5 days
15 days is 15/5 = 3 half lives
since half the amount is left in 5 days or 1 half life
(1/2) x (1/2) x (1/2) the staring amount would be left in
3 half lives. so 1/8 is left
(1/8) x 60.0 = 7.5 gm left
<span>The calculation of quantities in chemical equations are called Stoichiometry. Stoichiometry is a branch of chemistry which deals with relative quantities of reactants and products in chemical reactions. The correct answer is 'Stoichoimetry'. I hope this helps you. </span>
Answer:
The number of protons you welcome
Explanation:
Answer:
B. 0.2.
Explanation:
<em>n = mass/molar mass</em>
mass of CaCO₃ = 20 g, molar mass of CaCO₃ = 100.0869 g/mol.
<em>∴ n = mass/molar mass = </em>(20 g)/(100.0869 g/mol) <em>= 0.1998 ≅ 0.2 mol.</em>
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<em>So, the right choice is: B. 0.2.</em>
