Answer:
A
Explanation:
eons are divided into eras and eras are based on major events and can vary in time so eons can vary in time
The number of moles in a substance indicates the amount of the substance that contains the same number of particles as 12 g of the Carbon-12 isotope [or equivalent to 6.02 × 10²³] (which is used as a standard in the world of moles).
Now,
if 6.02 × 10²³ atoms are found in 1 mole ofsodium
then let 9.76 × 10¹² atoms are found in x
⇒ x = (9.76 × 10¹² ) ÷ (6.02 × 10²³)
= 1.619 × 10⁻¹¹ mol
Now, mass = moles × molar mass
∴ mass of Na = 1.619 × 10⁻¹¹ mol × 23 g/mol
= 3.72 × 10⁻¹⁰ g
Explanation:
Metals react with oxygen to form basic oxides while they react with water to form alkaline solutions. Also, acidic oxides are oxides of nonmetals and they react with water to form acidic solutions.
Trends on the period table shows the variation of metallic character as you move across and down the periodic table. Metallic character of a element decreases across the period on the periodic table from left to right because atoms readily accept electrons in their outermost shell to form stable configurations. Metallic character increases as you move down the group in the periodic table and this is because electrons become easier to lose as the atomic radius increases (more outer shells are added), where there is decreasing attraction between the nucleus and the valence electrons.
So down the group, the acidity of oxide reaction with water decreases because the oxides are more basic down the group while across the period, the acidity of oxide increases because acidic oxides are formed as we move across the period.
Answer:
2NaOH + CO2 -> Na2CO3 + H2O
1) Find the moles of each substance

2) Determine the limitting reagent

∴ Carbon dioxide is limitting as it has a smaller value.
3) multiply the limiting reagent by the mole ratio of unknown over known
n(H2O ) = 0.3976369007 × 1/2
= 0.1988184504 moles
4) Multiply the number of moles by the molar mass of the substance.
m = 0.1988184504 × (1.008 × 2 + 16.00)
= 0.1988184504 × 18.016
= 3.581913202 g
Explanation:
Answer is: 3,3 mol of <span>nitrous oxide gas is produced in this chemical reaction.
</span>Chemical reaction: N₂ + O₂ → 2NO.
n(N₂) = 1,65 mol.
n(NO) = ?
from reaction n(N₂) : n(NO) = 1 : 2.
1,65 mol : n(NO) = 1 : 2.
n(NO) = 3,3 mol.
n - amount of substance.