C I think it is c I think hope it issue
Answer : The correct option is, 11.77 L
Solution : Given,
Mass of bromine gas = 84 g
Molar mass of bromine gas = 159.8 g/mole
First we have to calculate the moles of bromine gas.

Now we have to calculate the volume of bromine gas at STP.
As we know that at STP,
1 mole of bromine gas contains 22.4 L volume of bromine gas
So, 0.5256 mole of bromine gas contains
volume of bromine gas
Therefore, the volume of bromine gas at STP is, 11.77 L
Answer is: the oxidation number of oxygen must decrease.
Oxidizing agent is element (substance) that gain electrons in chemical reaction.
For example, balanced chemical reaction: C + O₂ → CO₂.
Oxygen change oxidation number from 0 to oxidation number -2 (reduction) and carbon change from 0 to +4 (oxidation)
- Compounds are formed when two or more <u>elements</u> are chemically combined.
- When these elements are <u>chemically</u> combined, a new substance is formed with new chemical and physical <u>properties</u>.
- An element is a <u>pure</u> substance that cannot be separated into simpler substances by <u>physical</u> or chemical means.
- A compound is two or more elements <u>combined</u> chemically to produce a new substance.
- When two or more elements chemically combine, the compound has new properties, different from the chemical and physical properties of the <u>original</u> elements.
<h3>What is a chemical element?</h3>
A chemical element can be defined as a pure substance which comprises atoms that have the same atomic number (number of protons) in its nuclei and as such it is the primary constituent of matter.
Generally, some examples of a chemical element include the following:
- Argon.
- Sodium.
- Carbon.
- Oxygen.
- Hydrogen.
- Phosphorus
- Copper
- Aluminum
- Potassium
- Magnesium
<h3>What is a pure substance?</h3>
A pure substance can be defined as a single sample of matter that cannot be separated into other kinds of matter through the use of any physical or chemical separating technique because it has distinct chemical properties and a definite and constant composition.
Read more on pure substances here: brainly.com/question/2056940
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