Copper wire is not an example of a pure element because although it's made by pure elements, it's not one itself. It's made by factories.
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A because A is the only answer
Answer:
Hydrogen H₂ will be the limiting reagent.
The excess reactant that will be left after the reaction is 3.45 moles.
4.3 moles of water can be produced.
Explanation:
The balanced reation is:
2 H₂ + O₂ → 2 H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:
- H₂: 2 moles
- O₂: 1 mole
- H₂O: 2 moles
To determine the limiting reagent, you can use a simple rule of three as follows: if by stoichiometry 1 mole of O₂ reacts with 2 moles of H₂, how much moles of H₂ will be needed if 5.6 moles of O₂ react?

moles of H₂= 11.2 moles
But 11.2 moles of H₂ are not available, 4.3 moles are available. Since you have less moles than you need to react with 5.6 moles of O₂, <u><em>hydrogen H₂ will be the limiting reagent</em></u> and oxygen O₂ will be the excess reagent.
Then you can apply the following rules of three:
- If by reaction stoichiometry 2 moles of H₂ react with 1 mole of O₂, 4.3 moles of H₂ will react with how many moles of O₂?

moles of O₂= 2.15 moles
The excess reactant that will be left after the reaction can be calculated as:
5.6 moles - 2.15 moles= 3.45 moles
<u><em>The excess reactant that will be left after the reaction is 3.45 moles.</em></u>
- If by reaction stoichiometry 2 moles of H₂ produce 2 moles of H₂O, 4.3 moles of H₂ produce how many moles of H₂O?

moles of H₂O= 4.3 moles
<u><em>4.3 moles of water can be produced.</em></u>
Answer:
Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. Hope it helps ;)
The mass percent of each compound is
- (NaBr*2H2O)=85.71 percent
- (MgBr2*6H2O)=14.29 percent
<h3>The mass percent equation is as follows.</h3>
The formula mass percent is the most effective way to express mass percent: mass percent = (mass of chemical x total mass of compound) times 100. Add 100 to the top value to get the value expressed as a percentage.
<h3>What percentage by mass does a solution have?</h3>
By multiply the grams of solute per gram of solution by 100, it is possible to get the mass percent of a solution.
The molar mass of each element and the mass of each element contained in a mole of the compound are both solved for in the Mass Percent formula.
Learn more about Mass Percent here
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