Answer:- b. +3
Explanations:- Charge of a metal ion is equal to the number of valence electrons it has as it loses these electrons to have its nearest noble gas like electron configuration.
Al has 3 valence electrons and being a metal it loses all of these and so the charge of Al ion is +3. It could be shown as:

So, the right choice is b. 3+.
18. <span>Answer is </span>
A<span>
<span>Since the enthalpy of reaction is positive, the
forward reaction is<span> an endothermic reaction which means the energy
is gained from the surrounding to happen the reaction. If the temperature
decreases, according to the </span></span>Le Chatelier's principle, the system tries to become equilibrium
by increasing temperature. Since forward reaction is endothermic (because of
the bond breaking), the backward reaction is exothermic (because of the bond
making) which releases the energy to the surroundings. This makes the increase
of temperature. So if the backward reaction is promoted because of the decrease
of temperature, then the concentration of H</span><span>₂ will decrease.</span>
<span>
</span>
19. Answer is A.
The reactant side
has 2 moles/molecules of reactants and the product side has 4 moles/molecules
of products which come from 1 N₂(g) and 3 H₂<span>(g). If the pressure is reduced in the system, according to the Le Chatelier's principle, the
system tries to increase the pressure. </span><span>Hence, forward
reaction is promoted because of the higher number
of molecules in product side. If the forward reaction is promoted, the
concentration of NH</span>₃(g) will decreased.
<span>20. </span>Answer is C.
If the concentration
of reactant is increased in the
system, according to the Le Chatelier's principle, the system tries
to reduce the concentration of that reactant. So if NH₃(g) concentration
is increased, then to be equilibrium, the forward reaction will be promoted.
Then the concentration of N₂<span>(g) will increase.</span>
<span> </span>
Answer:
high less air cause there is no trees and lower is the same
Explanation:
its A. Genes make up chromosomes. it did it on study island..... i did the other answer the other person got and i got it wrong....and then it told me it was A. Genes make up chromosomes.
HOPE I COULD HELP
when we convert 32.5 lb/in² to atmosphere, the result obtained is 2.21 atm
<h3>Conversion scale</h3>
14.6959 lb/in² = 1 atm
<h3>Data obtained from the question</h3>
- Pressure (in lb/in²) = 32.5 lb/in²
- Pressure (in ATM) =?
<h3>How to convert 32.5 lb/in² to atm</h3>
14.6959 lb/in² = 1 atm
Therefore
32.5 lb/in² = 32.5 / 14.6959
32.5 lb/in² = 2.21 atm
Thus, 32.5 lb/in² is equivalent to 2.21 atm
Learn more about conversion:
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