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Flura [38]
2 years ago
7

2. Which of the most abundant elements in Earth's crust are nonmetals?​

Chemistry
2 answers:
Zigmanuir [339]2 years ago
5 0

Answer:

Oxygen

Explanation:

The thing is, The most abundant of the other nonmetals in the Earth's crust is oxygen which is the single most abundant element in the Earth's crust

melisa1 [442]2 years ago
4 0

Answer:

it is oxygen

Explanation:

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Complete the following radioactive decay problem.<br>222 86 RN to 4 2 HE + ?​
Andreas93 [3]

Answer:

₈₆²²²Rn    →   ₈₄Po²¹⁸  +  H₂⁴

Explanation:

The given nuclear reaction shows alpha decay.

₈₆²²²Rn    →   ₈₄Po²¹⁸  +  H₂⁴

Properties of alpha radiations:

Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4  and atomic number less than 2 as compared to parent atom the starting atom.

Alpha radiations can travel in a short distance.

These radiations can not penetrate into the skin or clothes.

These radiations can be harmful for the human if these are inhaled.

These radiations can be stopped by a piece of paper.

₉₂U²³⁸   →   ₉₀Th²³⁴  + ₂He⁴  + energy

8 0
3 years ago
Which isotope has the greatest number of protons?
tino4ka555 [31]

Answer:

The isotope with the greatest number of protons is:

  • <u>option D:  Pu-239, with 94 protons</u>

Explanation:

The number of <em>protons</em> is the atomic number and is a unique number for each type of element.

You can tell the number of protons searching the element in a periodic table and reading its atomic number.

Thus, this is how you tell the number of protons or each isotope

Sample       Chemical symbol  Element       atomic number   # of protons

A Pa-238       Pa                         protactinium         91                        91

B U-240         U                          uranium                 92                       92

C Np-238       Np                        neptunium            93                       93

D Pu-239        Pu                        plutonium              94                       94

8 0
3 years ago
The goal of this lesson:
mote1985 [20]

Answer:

1. The concentration of N₂O₄ decrease as the temperature of the system increased.

2. The formation of products was favored by the addition of heat.

3. The reaction going from right to left is exothermic.

4. N₂O₄ → 2NO₂; HR = +14 kcal.

Explanation:

Equation of the reaction is as follows: N₂O₄ ⇄ 2NO₂

The forward reaction proceeds with an increase in temperature. As the temperature of the reaction was increased, more of the N₂O₄ decomposed to form NO₂. Therefore, the concentration of N₂O₄ deceased.

2. The formation of products, that is the forward reaction leading to formation of NO₂ was favored by the addition of heat. Thus, with increase in temperature, the concentration of NO₂ increased.

3. An endothermic reaction is a type of reaction which requires energy input in the form of heat in order to proceed.

From the observations during the reaction, an increase in temperature by the addition of heat resulted in an increase in the forward reaction, therefore, the forward reaction is endothermic and the backward reaction is exothermic. Thus, the reaction in which colorless N₂O₄ is produced, is an exothermic reaction.

4. The change in enthalpy of a reaction is the difference in the heat content of reactants and products. For exothermic reactions, enthalpy change is negative, whereas for endothermic reactions, enthalpy change is positive.

The decomposition of  N₂O₄ to NO₂ is an endothermic reaction. Hence, the correct chemical equation is: N₂O₄ → 2NO₂; HR = +14 kcal.

7 0
3 years ago
Which of these is found in the energy levels of an atom?
Paul [167]

Answer:

Electrons

Explanation:

Because the nucleas is In the middle and the Electrons surround it

3 0
2 years ago
How many moles of sodium (Na) are there in a<br> sample of 5.87 x 1024 atoms of sodium?
Leno4ka [110]
9.74x 2351 that's the answer
6 0
3 years ago
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