As per the given chemical formula- Na2CO3.10H2O, one mole of the chemical compound contains 13 moles of oxygen atoms. Hence
Number of moles of oxygen atoms in one mole of Na2CO3.10H2O = 13
number of moles of oxygen atoms in 0.2 moles of Na2CO3.10H2O = 13 X 0.2 = 2.6
Now, one mole of a substance contains 6.022 X 10^23 particles of the substance. Thus
number of atoms of oxygen in one mole of oxygen atom = 6.022 X 10^23
number of moles of oxygen atoms in 2.6 moles of oxygen atoms = 2.6 X 6.022 X 10^23 = 15.657 X 10^23
= 1.566 X 10^24
Thus, there are 1.566 X 10^24 atoms of oxygen in 0.2 moles of Na2CO3.10H2O.
4.7
Answer:
₂He⁴
Explanation:
Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4 and atomic number less than 2 as compared to parent atom the starting atom.
Properties of alpha radiation:
Alpha radiations can travel in a short distance.
These radiations can not penetrate into the skin or clothes.
These radiations can be harmful for the human if these are inhaled.
These radiations can be stopped by a piece of paper.
₉₂U²³⁸ → ₉₀Th²³⁴ + ₂He⁴ + energy
ANSWER

EXPLANATION
Given that;
The two reactants are KBr and CaO
Double replacement reaction is a type of chemical reaction that occur when two reactants exchange cations and anions to yield new products.

Therefore, the resulting products of the given data are K2O + CaBr2
The correct answer is option B
Answer:
carbon dioxide is acidic and when it comes in contact with blue litmus paper it turns red
Explanation:
Answer:
1. KNO3
2. Ca(NO3)2
3. CaCl2
4. KCl
Explanation:
In each of the neutralization reactions, the H from one of the reactant(acid) will combine with the OH from the other reactant (base) to form water while the other elements combine to give the salt as shown below:
1. HNO3 + KOH → H2O + KNO3
The salt produced is KNO3
2. 2HNO3 + Ca(OH)2 → 2H2O + Ca(NO3)2
The salt produced is Ca(NO3)2
3. 2HCl +Ca(OH)2 → 2H2O + CaCl2
The salt produced is CaCl2
4. HCl +KOH → H2O + KCl
The salt produced is KCl