<u>Answer:</u> The isotopic symbol of barium is
and that of strontium is 
<u>Explanation:</u>
Nuclear fission reactions are defined as the reactions in which a heavier nuclei breaks down in two or more smaller nuclei.
In a nuclear reaction, the total mass and total atomic number remains the same.
- For the given fission reaction:

Total mass on reactant side = total mass on product side
235 + 1 = A + 94 + 3
A = 139
Total atomic number on reactant side = total atomic number on product side
92 + 0 = Z + 36 + 0
Z = 56
The isotopic symbol of barium is 
- For the given fission reaction:

Total mass on reactant side = total mass on product side
235 + 1 = A + 143 + 3
A = 90
Total atomic number on reactant side = total atomic number on product side
92 + 0 = Z + 54 + 0
Z = 38
The isotopic symbol of strontium is 
Hence, the isotopic symbol of barium is
and that of strontium is 
<h3>
Answer:</h3>
2.125 g
<h3>
Explanation:</h3>
We have;
- Mass of NaBr sample is 11.97 g
- % composition by mass of Na in the sample is 22.34%
We are required to determine the mass of 9.51 g of a NaBr sample.
- Based on the law of of constant composition, a given sample of a compound will always contain the sample percentage composition of a given element.
In this case,
- A sample of 11.97 g of NaBr contains 22.34% of Na by mass
A sample of 9.51 g of NaBr will also contain 22.345 of Na by mass
% composition of an element by mass = (Mass of element ÷ mass of the compound) × 100
Mass of the element = (% composition of an element × mass of the compound) ÷ 100
Therefore;
Mass of sodium = (22.34% × 9.51 g) ÷ 100
= 2.125 g
Thus, the mass of sodium in 9.51 g of NaBr is 2.125 g
Answer:
H2O is a compound because its a main constitute of earths hydrosphere
The sample with the largest number of oxygen atoms will be calcium perchlorate.
<h3>Number of atoms in a compound</h3>
Since we are not looking at the number of moles, the mass of the compounds has no bearing on the number of atoms of oxygen.
- The chemical formula for carbon dioxide is
. Thus, it has 2 atoms of oxygen. - The chemical formula for potassium chlorate is
. Thus, it has 3 oxygen atoms. - The chemical formula for calcium perchlorate is
. Thus, it has 8 atoms of oxygen. - The chemical formula for sodium hydroxide is NaOH. Thus, it has 1 atom of oxygen.
Therefore, the compound with the largest number of oxygen atoms is calcium perchlorate.
More on the number of atoms in compounds can be found here: brainly.com/question/1686912
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