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2 years ago

What is the difference between mass number and atomic number

2 answers:

7 0

Mass number is the number of protons and neutrons in an atom.
Atomic mass is the average mass of all the isotopes of a certain type.

myrzilka [38]2 years ago

5 0

Atomic number is the number of protons that are inside that atom. This helps identify which element an atom is.

Atomic mass is the number of protons and neutrons inside an atom.

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In which cell structure does MOST of the process of cellular respiration take place?

ahrayia [7]

Mitochondria are rod-shaped organelles are basically considered the power producers of the cell, it converts oxygen and nutrients into adenosine triphosphate or ATP, which is the chemical energy,also known as "currency" of the cell which powers the metabolic actions of the cell. This process is called aerobic respiration and it is the reason animals breathe oxygen. Cellular repiration happens in the mitochodrion. The 3 phases of cellular respiration are Krebs Cycle, Electron Transport and Glycolysis (Fermentation). Glycolysis takes place in the cytoplasm while the Krebs cycle and electron transport take place in the mitochondria.

6 0

3 years ago

Consider the following mechanism for the oxidation of bromide ions by hydrogen peroxide in aqueous acid solution. H+ + H2O2 ? H3

Margarita [4]

Answer: The rate law for the reaction is $\text{Rate}=k'[H+][H_2O_2][Br^-]$

Explanation:

Rate law is the expression which is used to express the rate of the reaction in terms of the molar concentration of reactants where each term is raised to the power their stoichiometric coefficient respectively from a balanced chemical equation.

In a mechanism of the reaction, the slow step in the mechanism determines the rate of the reaction.

The chemical equation for the oxidation of bromide ions by hydrogen peroxide in aqueous acid solution follows:

$2H^++2Br^-+H_2O_2\rightarrow Br_2+2H_2O$

The intermediate reaction of the mechanism follows:

Step 1: $H^++H_2O_2\rightleftharpoons H_3O_2^+;\text{ (fast)}$

Step 2: $H_3O_2^++Br^-\rightarrow HOBr+H_2O;\text{(slow)}$

Step 3: $HOBr+H^++Br^-\rightarrow Br_2+H_2O;\text{(fast)}$

As, step 2 is the slow step. It is the rate determining step

Rate law for the reaction follows:

$\text{Rate}=k[H_3O_2^+][Br^-]$ ......(1)

As, $[H_3O_2^+]$ is not appearing as a reactant in the overall reaction. So, we apply steady state approximation in it.

Applying steady state approximation for $[H_3O_2^+]$ from step 1, we get:

$K=\frac{[H_3O_2^+]}{[H^+][H_2O_2]}$

$[H_3O_2^+]=K[H^+][H_2O_2]$

Putting the value of $[H_3O_2^+]$ in equation 1, we get:

$\text{Rate}=k.K[H^+][H_2O_2][Br^-]\\\\\text{Rate}=k'[H+][H_2O_2][Br^-]$

Hence, the rate law for the reaction is $\text{Rate}=k'[H+][H_2O_2][Br^-]$

4 0

3 years ago

Classify each of these soluble solutes as a strong electrolyte, a weak electrolyte, or a nonelectrolyte. Solutes formula hydroch

matrenka [14]

Compounds which on dissolving in water gets completely dissociates into its ions are known as strong electrolytes whereas compounds which on dissolving in water gets partially dissociates into its ions are known as weak electrolytes.

Substances which gives solution on dissolving in water and do not dissociates into ions also does not conduct electric current are known as nonelectrolyte.

Hydrochloric acid, $HCl$

On adding $HCl$ (strong acid) in water, it will completely dissociates into ions ( $H^{+}$ and $Cl^{-}$ ) and thus, it is a strong electrolyte.

Sodium hydroxide, $NaOH$

On adding $NaOH$ (strong base) in water, it will completely dissociates into ions ( $Na^{+}$ and $OH^{-}$ ) and thus, it is a strong electrolyte.

Formic acid, $HCOOH$

On adding $HCOOH$ (weak acid) in water, it will partially dissociates into ions ( $H^{+}$ and $HCOO^{-}$ ) and thus, it is a weak electrolyte.

Methyl amine, $CH_3NH_2$

On adding $CH_3NH_2$ (weak base) in water, it will partially dissociates into ions ( $CH_3NH_3^{+}$ and $OH^{-}$ ) and thus, it is a weak electrolyte.

Potassium chloride, $KCl$

On adding $KCl$ in water, it will completely dissociates into ions ( $K^{+}$ and $Cl^{-}$ ) and thus, it is a strong electrolyte.

Ethanol, $C_2H_5OH$

On adding $C_2H_5OH$ in water, it will not dissociates into ions and thus, it is a nonelectrolyte.

Sucrose, $C_{12}H_{22}O_{11}$

On adding $C_{12}H_{22}O_{11}$ in water, it will not dissociates into ions and thus, it is a nonelectrolyte.

3 0

3 years ago

1. In general, the nucleus of a small atom is stable. Therefore, over very short distances, such as those in a small nucleus,

postnew [5]

<h3>1. Answer;</h3>

a. the strong nuclear force is much greater than the electric force.

<h3>Explanation;</h3>

For an atom to be stable it means it has enough amount of binding energy to hold its nucleus together permanently.
Therefore, an unstable atom lacks enough amount of binding energy to hold its nucleus permanently and thus undergoes decay to achieve stability. Unstable atoms are therefore referred to being radioactive.
Small atoms are stable; this is because they have equal number of protons and neutrons and thus the protons and neutrons fill up energy levels while maximizing the strong force binding the nucleus together.

<h3>9. Answer;</h3>

b. change into a different element altogether.

Uranium-238 undergoes alpha decay. Therefore, uranium-238 will change into a different element altogether.

<h3> Explanation;</h3>

Unstable atoms undergo radioactive decay in order to achieve stability of their nucleus.
Uranium-238 is an example of such atom, which may undergo decay to achieve stability.
Alpha decay is one of the types of decays, others being beta decay and gamma decay. In alpha decay the radioactive isotope undergoes decay such that its mass number is decreased by four and its atomic number is decreased by two.
Therefore, Uranium-238 undergoes alpha decay to form a different element whose mass number is 234 and atomic number is 90, known as thorium-234.

5 0

3 years ago

Read 2 more answers

What’s is solar energy

Sonja [21]

Solar energy is energy created from the sun

8 0

2 years ago

Read 2 more answers