Answer:
6.25%
Explanation:
Given data:
Half life of lutetium-117 = 6.75 days
Percentage remaining after 27 days = ?
Solution;
Number of half lives = Time elapsed / half life
Number of half lives = 27 days / 6.75 days
Number of half lives = 4
At time zero = 100%
At first half life = 100%/2 = 50%
At second half life = 50%/2 = 25%
At 3rd half life = 25%/2 = 12.5%
At 4th half life = 12.5%/2 = 6.25%
Answer: N = 2.78 × 10^23 atoms
There are N = 2.78 × 10^23 atoms in 70g of Au2cl6
Completed Question:
Calculate the number of gold atoms in a 70g sample of gold(III) chloride . Be sure your answer has a unit symbol if necessary, and round it to significant digits
Explanation:
Given:
Molar mass of Au2cl6 = 303.33g/mol
Mass of Au2cl6 = 70g
Number of moles of Au2cl6 = 70g/303.33g/mol = 0.231mol
According to the chemical formula of Au2cl6,
1 mole of Au2cl6 contains 2 moles of Au
Number of moles of Au = 2 × 0.231mol = 0.462mole
There are 6.022 × 10^23 atoms in 1 mole of an element.
Number of Atom of gold in 0.462 mole of gold is:
N = 0.462 mol × 6.022 × 10^23 atoms/mol
N = 2.78 × 10^23 atoms
Answer:
they are molecules with normal bonds rather than partial bonds and can occasionally be isolated.
Explanation:
In chemistry, reaction intermediates are species that are formed from reactants and are subsequently being transformed into products as the reaction progresses. In other words, reaction intermediates are species that do not appear in a balanced reaction equation but occur somewhere along the reaction mechanism of a non-elementary reaction. They are usually short lived species that possess a high amount of energy. They may or may not be isolated.
They are often molecular species with normal bonds unlike activated complexes that are sometimes hypervalent species.
Answer:
- 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Explanation:
<em>Photosynthesis</em> is the chemical process carried out by plants for the conversion of inorganic matter (carbon dioxide and water) into organic matter (glucose) with the release of oxygen, using light (sun energy).
So the chemical process may be represented by:
carbon dioxide + water + sun energy → glucose + oxygen
- <u>Skeleton equation:</u>
CO₂ + H₂O + sun energy → C₆H₁₂O₆ + O₂
- <u>Balanced chemical equation:</u>
6CO₂ + 6H₂O + sun energy → C₆H₁₂O₆ + 6O₂
- <u>Supressing the energy to show only the chemical compounds:</u>
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
