<u>Answer:</u> The additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
<u>Explanation:</u>
To calculate the mole percent of a substance, we use the equation:

Mass percent means that the mass of a substance is present in 100 grams of mixture
To calculate the number of moles, we use the equation:

We require the molar masses of Z and X to calculate the mole percent of Z and X respectively
Hence, the additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
Answer:
32.23 to 4 significant figures.
Explanation:
The molar mass of the element is the mass of 6.022 * 10^23 atoms (Avogadro's number).
So by proportion it is 6.022 * 10^23 * 3.88 / 7.25 * 10^22
= 32.23 to 4 significant figures.
Answer:
Bubbling/Foaming
Heat is produced
Explanation:
A chemical reaction has occurred if
1. There is a change in colour
2. Formation of a precipitate
3. Formation of a gas
4. Change in temperature
5. Change of smell
In the reaction of hydrogen peroxide and potassium iodide, the solution quickly rises which shows the formation of gas. This means it is a chemical reaction.
The beaker/test tube/whatever you used should also become warm because it is an exothermic reaction. This means its a chemical reaction
<span>Friction creates heat which in turn can lead to deviations from the original size and shape of a part.
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