Answer:
Explanation:
To convert atoms to moles, Avogadro's Number must be used: 6.022*10²³.
This tells us the amount of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case it is the atoms of potassium. We can create a ratio.
Multiply by the given number of moles: 15.2
The moles of potassium cancel.
The denominator of 1 can be ignored.
Multiply.
The original measurement of moles has 3 significant figures, so our answer must have the same. For the number we calculated that is the hundredth place. The 3 in the thousandth place tells us to leave 5.
In 15.2 moles of potassium, there are <u>9.15*10²⁴ atoms of potassium.</u>
The answer will be A & B not only because it makes sense but evaporation is taking water away not adding to (gaining)
A scientific law is a statement that is universally accepted and answers the "how?" question.
Hope this helps!
Answer:
b) C = 0.50 J/(g°C)
Explanation:
∴ Q = 50 J
∴ m = 10.0 g
∴ ΔT = 35 - 25 = 10 °C
specific heat (C) :
⇒ C = Q / mΔT
⇒ C = 50 J / (10.0 g)(10 °C)
⇒ C = 0.50 J/(g°C)
Answer is: <span>the charge of the iron in this compound is +2.
Atomic mass of iron is 55,8 g/mol.
Atomic mass of chlorine is 35,5 g/mol.
If compound is FeCl, molar mass would be 55,8 </span>g/mol + 35,5 g/mol = 91,3 g/mo, that is not correct.
If compound is FeCl₂, malar mass of compound would be:
55,8 g/mol + 2·35,5 g/mol = 126,8 g/mol, that is correct.
Oxaidation number of chlorine is -1.