Answer:
You're going to have to convert the grams to moles, and then multiply that with the ratio of heat produced to the ratio of CH4
The answer is C. Assume specific heat to be 4.18 J/g/C
Half-life of a radioactive substance is the time required to reduce the amount of substance to half of its initial amount.
In present case, half-life is material is given as 1000 years and initial amount of material is given as 400 kg
Answer 1) Since, half-life of radio-active substance is 1000 years, therefore after 1st half life, amount of the material will be left to half the initial amount. Hence, amount of substance left after 1000 years = 400/2 = 200 kg.
Answer 2) For 2000 years, radioactive material has crossed 2 times the half life. Therefore , amount of the material will be left to 1/4 the initial amount. Hence, amount of substance left after 2000 years = 400/4 = 100 kg.
Answer 3) For 4000 years, radioactive material has crossed 4 times the half life. Therefore , amount of the material will be left to 1/16 the initial amount. Hence, amount of substance left after 4000 years = 400/16 = 25 kg.
Answer:
2.41065 grams
Explanation:
Here we have to apply molarity, particularly in reference to the equation molarity = moles of solute / volume. I would like to rewrite this formula, but with respect to the units - grams = moles / Liters,
We can use molarity to determine the number of moles. After doing so, we can determine the mass of the solute with respect to the formula moles = mass / molar mass. The molar mass of NaCl is 58.44 grams.
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275 mL = 0.275 L,
Number of Moles of NaCl = 0.150 * 0.275 = 0.04125 moles,
Mass = 0.04125 * 58.44 = 2.41065 grams,
Solution - Mass of NaCl = 2.41065 grams
<u><em>Hope that helps!</em></u>
Answer:
The Bohr model of the atom explains the reactivity of all atoms.
