Answer is: <span>volume of balloon is </span>476,85 cm³.
density of air: d(air) = -0,0043 · 18,0°C + 1,2874.
d(air) = 1,21 kg/m³ = 1,21 · 10³/ 10⁶ = 0,00121 g/cm³.
m(balloon) = 0,577 g.
d(balloon) = d(air).
d(balloon) = m(balloon) ÷ V(balloon).
V(balloon) = m(balloon) ÷ d(balloon)
V(balloon) = 0,577 g ÷ 0,00121 g/cm³.
V(balloon) = 476,85 cm³.
Answer:
Atoms X and Atom Y are isotope is right answer
Answer:
pH is an index of how many protons, or hydrogen ions (H+) are dissolved and free in a solution. The pH scale goes from 0 to 14. A fluid with a pH of 7 is neutral. Below 7, it is acidic; above 7, it is alkaline.
The more below or above 7 a solution is, the more acidic or alkaline it is. The scale is not linear—a drop from pH 8.2 to 8.1 indicates a 30 percent increase in acidity, or concentration of hydrogen ions; a drop from 8.1 to 7.9 indicates a 150 percent increase in acidity. Bottom line: Small-sounding changes in ocean pH are actually quite large and definitely in the direction of becoming less alkaline, which is the same as becoming more acidic.
If you think about it, we use descriptive words like this all the time. A person who stands 5’5” tall and weighs 300 pounds isn’t thin. If he loses 100 pounds, he still won’t be thin, but he will be thinner than he was before he went on the diet. (And we are more likely to comment that he’s looking trimmer than to say he’s not as fat as he used to be.)
Answer: Out of the given options bonds connecting atoms in reactants break, and bonds connecting atoms in products form are the changes which takes place when a chemical change occurs.
Explanation:
A change that leads to the change in chemical composition of a substance is called a chemical change.
For example, 
Here, bond between the reactant atoms nitrogen and hydrogen is broken down.
On the other hand, bond connecting the products that is 
and 
is formed.
Thus,, we can conclude that out of the given options bonds connecting atoms in reactants break, and bonds connecting atoms in products form are the changes which takes place when a chemical change occurs.
