Answer:
C. 70%
Explanation:
Atomic Mass of the silicon = 28 g.
Atomic mass of the Carbon = 12 g.
Total mass of the Silicon Carbide = 28 + 12
= 40 g.
Now, Using the formula.
% Composition = Mass of the silicon/Total mass of the compound × 100 %
= 28/40 × 100 %
= 70 %
Hence, % composition of the silicon in SiC is 70%
Name for the compound HF is Hydrogen fluoride.
Hope this helps!
Answer:
Hg(NO₃)₂(aq) + Na₂SO₄(aq) → 2NaNO₃(aq) + HgSO₄(s)
Moles of Hg(NO₃)₂ = 55.42 / 324.7 ==> 0.1707 moles
Moles of Na₂SO₄ = 16.642 / 142.04 ==> 0.1172 moles
Limiting reagent is Na₂SO₄ as it controls product formation
Moles of HgSO₄ formed = 0.1172 moles
= 0.1172 x 296.65
= 34.757g
Explanation:
Half-life is the time taken for the concentration of the substance to reduce by 50%. The original sample of strontium had a mass of 1.6 gms. Thus, option d is correct.
<h3>What is half-life?</h3>
The half-life of any radioactive substance is the time period at which the concentration will get reduced to half the initial amount. The initial mass of Sr-90 is calculated as,

Given,
Quantity of the remaining substance N (t) = 0.40 gm
Initial radioactive substance quantity
=?
Time duration (t) = 56 years
Half-life = 28 years
Substituting values above:

= 1.6 gm
Therefore, option d. the initial mass of Sr is 1.6 gm.
Learn more about half-life here:
brainly.com/question/16145921
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The answer is, <span>The Himalayan mountain range and </span>Tibetan plateau<span> have formed as a result of the collision between the </span>Indian Plate<span> and </span>Eurasian Plate<span> which began 50 million years ago and continues today.</span>