Answer:
The correct answer is - 3.012×10^23 molecules
Explanation:
The number of molecules is present in any mole of an element or compound are the same. To find the molecules you need to multiply the number of the moles of the compound by Avogadro's number:
Moles are calculated from the molecular weight, for AlF3
= 26.98 + 3×19
= 26.98 + 57
= 83.98
Then moles in 42 grams:
= 42/83.98
= 0.5001190 moles
Now the number of molecules = moles*Avogadro's number
= 0.500110×6.022×10^23
= 3.011×10^23 molecules
Answer is: 1160 J of heat Is required to increase the temperature.
m(Fe) = 100 g.
∆T = 40,2 - 15 = 25,2°C.
C(Fe) = 0,46 J/g•°C.
Q = m(Fe) • C • ∆T.
Q = 100 g • 0,46 J/g•°C • 25,2°C
Q = 1160 J.
C - specific heat.
Answer is (2) - hydrogen carbonate
<em>Explanation:</em>
NaHCO₃ is an ionic compound which is made from Na⁺ and HCO₃⁻ ions. The decomposition is
NaHCO₃ → Na⁺ + HCO₃⁻
Among the resulted ions, Na⁺ is a monatomic ion while HCO₃⁻ is a polyatomic ion.
<em>Polyatomic ions mean ions which are made of two or more different atoms.</em>
HCO₃⁻ is made from 3 atoms as H, C and O. The name of HCO₃⁻ ion is bicarbonate or hydrogen carbonate.
Answer:
The answer is the Sodium Chloride.
Explanation:
A solute is the minor component in a solution, dissolved in the solvent, and the sodium is being dissolved in water ( or the solvent).
