Answer:
Number of moles = 0.05 mol
Explanation:
Given data:
Mass of Pb = 10.5 g
Number of moles of Pb = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of Pb is 207.2 g/mol.
Now we will put the values in formula.
Number of moles = 10.5 g/207.2 g/mol
Number of moles = 0.05 mol
A chemical equation is a short hand expression of a chemical reaction. There aretwo<span> parts to a chemical equation. The reactants are the elements or compounds on the left side of the arrow (-->). The elements and compounds to the right of the arrow are the products.</span>
Actually, that does not happen until the protostar becomes a star when nuclear ignition starts and is maintained. It takes awhile for new star to go through its T-Tauri stage and settle down on the main sequence.
<span>A STAR does not reach hydrostatic equilibrium until it on the main sequence. Otherwise, it would remain a brown dwarf with not enough mass to to maintain nuclear fusion for more than 3,000 to 10,00 years. </span>
Answer:
John Dalton
Explanation:
John Dalton in 1808 suggested that all matter consists of tiny particles called atoms and that the atoms of a specific element are identical.
He postulated the Dalton's atomic theory which has the following important parts;
- All matters consists of indivisible particles called atoms
- Atoms of the same element are similar and are different from atoms of other elements.
- Atoms can neither be created nor destroyed.
- Atoms combine in simple whole ratios to form compounds.