A. The mass of one mole of the virus is calculated by multiplying the mass of a single virus by the Avogadro's number which is equal to 6.022 x 10^23. Performing this operation,
mass = (9.0 x 10^-12 mg)(6.022 x 10^23) = 5.42 x 10^12 mg
In correct number of significant figures, the answer would only have to be 5.4 x 10^12 mg.
b. The number of moles of the virus that will have the same mass as the oil tanker is calculated by dividing the mass of the oil tanker by the mass of one mole of the virus. Note that doing division, both would have to have the same units.
n = (3.0 x 10^7 kg) / (5.4 x 10^12 mg)(1 g/1000 mg)(1 kg/1000 g)
Simplifying,
n = 6
In correct number of significant figures, the answer is 6.0.
Answer:
HNO₃ (aq) —> H⁺ (aq) + NO₃¯ (aq)
Explanation:
From the question given above
HNO₃ + H₂O —> ?
Nitric acid, HNO₃ reacts with water, H₂O to form aqueous solution of nitric acid as illustrated below:
HNO₃ + H₂O —> HNO₃ (aq)
Nitric acid is a strong acid and, so will ionised completely when dissolved in water. This is illustrated below:
HNO₃ (aq) —> H⁺ (aq) + NO₃¯ (aq)
Are you kidding me is this answer or question you got be kidding
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical equation for reaction of potassium superoxide with carbon dioxide to produce oxygen and potassium carbonate will be:

Suprysingly , Humans can survive weather well since we wear clothing.
A good estimate of how cold a human can survive would be in the range of -50 or lower.
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