Answer:
5.50 moles of magnesium oxide is 221.6742 grams
Explanation:
to do this you multiply the number of moles by the molar mass
Answer:
1.18×10²³ atoms.
Explanation:
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ atoms.
From the above concept, 1 mole of sodium also contains 6.02×10²³ atoms.
1 mole of sodium = 23 g.
Thus,
23 g of sodium contains 6.02×10²³ atoms.
Therefore, 4.5 g of sodium will contain = (4.5 × 6.02×10²³)/23 = 1.18×10²³ atoms.
From the above calculation,
4.5 g of sodium contains 1.18×10²³ atoms.
Answer:
The answer is
<h2>2 cm/year</h2>
Explanation:
To find the rate in cm/year we must first convert 200 m into cm
1 m = 100 cm
if 1 m = 100 cm
Then 200 m = 200 × 100 = 20 ,000 cm
So the rate is
<h2>
</h2>
<u>Reduce the fraction with 10,000</u>
We have the final answer as
<h3>2 cm/year</h3>
Hope this helps you
Answer:
exothermic reaction
Explanation:
If there is a drop in temperature, then energy was lost to the surroundings because temperature is the average measure of kinetic energy. An exothermic reaction would result in this lost of energy. An endothermic reaction would absorb energy and make the temperature rise.
Answer:
+1.03 V
Explanation:
The standard emf of the voltaic cell is the value of the standard potential of it, which is calculated by the standard reduction potential (E°).
The standard reduction potential is the potential needed for the reduction reaction happen, and it's determined by the reaction with the hydrogen cell (which has E° = 0.0V). The half-reactions of reduction of Ni⁺² and Ag⁺, are:
Ni⁺²(aq) + 2e⁻ → Ni(s) E° = -0.23 V
Ag⁺(aq) + e⁻ → Ag(s) E° = +0.80 V
The value is calculated by a spontaneous reaction, in which the cell with the greater E° is reduced (gain electrons), and the other is oxidized (loses electrons). So, Ag⁺ reduces.
emf = E°reduces - E°oxides
emf = 0.80 - (-0.23)
emf = +1.03 V
