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3 years ago

Question 2

Chemistry

1 answer:

azamat3 years ago

8 0

Answer:

Explanation:

For A, 2Al(OH)3 contains 6H on the left side of the equation but only has 3H on the right side of the equation, thus its not balanced

For B, there is 2(Al2), which is 4, on the left side of the equation but only 2Al on the right side of the equation, so it is not balanced.

For D, theres a total of 6 H on the left side of the equation as there is (OH)3 and 3H, but none of the right side, so its not balanced.

C is the correct answer as

on the left side of the equation:

2 Al(OH)3 has 2Al, 6O, and 6H

on the right side of the equation:

Al2O3 has 2Al and 3O

3 H20 has 3H and 6O

this makes a total of 2Al, 6H and 6O, which is equal to the number of each element in the left side, thus it is balanced and is the right answer.

In the future for these type of qns, you want to add up the number of each element on the left, then the ride, and see compare the numver of element they have. if the number of all the elements on both sides are the same, the equation is balanced.

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Answer:

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Explanation:

Given data:

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Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

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The number of positive changes in the nucleus of an atom is equal to

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Answer:

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An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.

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The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.

Symbol= e⁻

Mass= 9.10938356×10⁻³¹ Kg

It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.

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Neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.

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For example

The carbon have six protons and six neutrons so its atomic mass is 12 amu and atomic number is six.

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