Answer:

Explanation:
1. First take the cylinder volume formula:

2. Then take the values for the radius and the height of the cylinder and replace them into the formula:

3. Solve the equation:



Answer:
14.77 mol.
Explanation:
- It is known that every 1.0 mole of compound or element contains Avogadro's number (6.022 x 10²³) of molecules or atoms.
<u><em>Using cross multiplication:</em></u>
1.0 mole of He contains → 6.022 x 10²³ atoms.
??? mole of He contains → 8.84 x 10²⁴ atoms.
<em>∴ The no. of moles of He contains (8.84 x 10²⁴ atoms) </em>= (1.0 mol)(8.84 x 10²⁴ atoms)/(6.022 x 10²³ atoms) =<em> 14.77 mol.</em>
Answer:
a new substance is formed, if heat is formed, color change, the evolution of gas, and bubbles or fizzing