Answer:
Element X with atomic number 10 and atomic mass 21
Element Z with atomic number 10 and atomic mass 22
Explanation:
Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
- Isotopes of an element have the same electronic configuration.
- They share the same chemical properties
- They only differ in their masses.
So, Element X and Z with atomic number 10 which is their number of electrons are isotopes. Their mass number, 21 and 22 differs.
1.422 × 10^11 us liquid gallons
TRUE its glucose if they have sunlight
Answer:
b. 3.66x10²³ atoms of chromium.
Explanation:
First we calculate how many moles are there in 31 grams of chromium, using its molar mass:
- Molar Mass of Chromium = 51 g/mol (This can be found on any periodic table)
- 31 g ÷ 51 g/mol = 0.608 mol
Then we <u>calculate how many atoms are there in 0.608 moles</u>, using <em>Avogadro's number</em>:
- 0.608 mol * 6.023x10²³ atoms/mol = 3.66x10²³ atoms
The correct answer is thus option b. 3.66x10²³ atoms of chromium.
Answer:
16.8 g of AgCl are produced
Explanation:
The reactants are: NaCl and AgNO₃
The products are: AgCl, NaNO₃
Balanced equation: NaCl(aq) + AgNO₃(aq) → NaNO₃(aq) + AgCl(s) ↓
We convert the mass of AgNO₃ to moles → 10 g / 85g/mol = 0.117 moles
Ratio is 1:1, therefore 0.117 moles of nitrate will produce 0.117 moles of AgCl.
According to stoichiormetry.
We convert the moles to mass → 0.117 mol . 143.3g /1mol = 16.8 g