Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions
Answer:
c) 9.03 x 10^23
Explanation:
find the molar mass of Al
Al is 27.0 grams
Then use that, to find the number of moles in Aluminum.
Then use Avogadro's number which is 6.02 * 10^23
After that, write all of that down with dimensional analysis.
40.5 g * 1 mol/ 27.0 g of Al * 6.02 x 10^23 / 1mol
As your final answer, you will get 9.03 * 10^23 atoms with sig figs.
Hope it helped!
The number of moles of gas present are 0.0054
<u>Explanation:</u>
Given-
Temperature, T = 100°C = 100 + 273 = 373K
Volume, V = 0.044L
Pressure, P = 3.81 atm
Moles of gas, n = ?
We know,
PV = nRT
R = 0.082 L.atm.K⁻¹.mol⁻¹
n = PV/RT
n = (3.81)(0.044)/(0.082)(373)
n = 0.0054 moles
Therefore, number of moles of gas present are 0.0054
Answer:
It would require 80 g of NaOH .
Explanation: