Physical change because it's only changing the shape of the gold.
Answer:
B?
Explanation:
In the example, the amount of hydrogen is 202,650 x 0.025 / 293.15 x 8.314472 = 2.078 moles. Use the mass of the hydrogen gas to calculate the gas moles directly; divide the hydrogen weight by its molar mass of 2 g/mole. For example, 250 grams (g) of the hydrogen gas corresponds to 250 g / 2 g/mole = 125 moles.
Answer:
<h2>0.06 % </h2>
Explanation:
The percentage error of a certain measurement can be found by using the formula

From the question
error = 500 - 499.7 = 0.3
actual volume = 500 mL
We have

We have the final answer as
<h3>0.06 % </h3>
Hope this helps you

The reaction creates dihydrogen, hence if it's uncontrolled it could lead to potentially dangerous amounts of gas being released at once.
Group 8 elements. They are unreactive and stable