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Korvikt [17]
4 years ago
5

An unknown is discovered to have three isotopes. 25% have a mass of 86.0, 66% have a

Chemistry
1 answer:
7nadin3 [17]4 years ago
7 0
It’s obvious that it’s 13 because 89 - 92 =13
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Ammonia (NH3(g), es001-1.jpgHf = –46.19 kJ/mol) reacts with hydrogen chloride (HCl(g), es001-2.jpgHf = –92.30 kJ/mol) to form am
SIZIF [17.4K]
Answer is: enthalpy for this reaction is -175.91 kJ.
Chemical reaction: NH₃ + HCl → NH₄Cl.
ΔrH = ∑ΔfH(products of reaction) - ∑ΔfH(reactants).
ΔrH = ΔfH(NH₄Cl) - (ΔfH(NH₃) + ΔfH(HCl)).
ΔrH = -314.4 kJ/mol · 1 mol - (-46.19 kJ/mol · 1 mol + (-92.30 kJ/mol) · 1 mol).
ΔrH = -314.4 kJ + 138.49 kJ.
ΔrH = -175.91 kJ.
5 0
4 years ago
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What is irrigation?Describe two methods of irrigation which conserve water​
MA_775_DIABLO [31]

The process of watering the crops is called irrigation.

Any two methods of irrigation are:

<h3>(i) Sprinkler system:</h3>

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<h3> (ii) Drip irrigation:</h3>

This system is used to save water as it allows the water to flow drop by drop at the roots of the plants. It is the best technique for watering fruit plants, gardens and trees. Water is not wasted at all.

5 0
3 years ago
Pls help!!! I will mark you as brainliest if you answer the question!!
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1 — Element D and A ( Which are Sodium and aluminium )

2 — ( 2 + 8 + 3 = 13 electrons total ) Element A Because it's atomic number is 13.

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4 — Element F , which is hydrogen. ( Hydrogen is the only element to not have any neutron )

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6 — The element F ( Which is hydrogen ) Don't contain any neutron.

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3 years ago
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Answer: yes

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3 years ago
Write any two uses of fractinal distillation​
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Fractional distillation is used for the purification of water as well as separating acetone and water.

Fractional distillation is used in several industries like oil refineries and chemical plants mainly for purification and separation of many organic compounds.

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