This question is about Avogadro's number.
Avogadro's number is the number is 6.022 * 10^23.
That means that 1 mol of molecules is 6.022 * 10^23 molecules, so 4 moles is 4 * 6.022 * 10^23 molecules = 24.088 * 10^23 molecules = 2.4088 * 10^24 molecules.
Answer: 2.4088 * 10^24 molecules.
Answer:
Changes in colour of litmus paper.
- Blue litmus turns red under acidic conditions.
- Red litmus turns blue under basic conditions.
Noe
PH values:-
K is acidic as pH is <7
Hence K will change the colour of blue litmus paper.
#B
Examples of substances
- K=Vinegar, Tomatoes.
- M=Milk of magnesia,Soap
Answer:
The percent composition is 21% N, 6% H, 24% S and 49% O.
Explanation:
1st) The molar mass of (NH4)2SO4 is 132g/mol, and it represents the 100% of the mass composition.
In 1 mole of (NH4)2SO4, there are:
- 2 moles of N.
- 8 moles of H.
- 1 mole of S.
- 4 moles of O.
2nd) It is necessary to calculate the mass of each element, multiplying its molar mass by the number of moles:
- 2 moles of N (14g/mol) = 28g
- 8 moles of H (1g/mol) = 8g
- 1 mole of S (32g/mol) = 32g
- 4 moles of O (16g/mol) = 64g
3rd) With a mathematical rule of three we can calculate the percent composition of each element in the molecule of (NH4)2SO4:




In this case, we can calculate the percent composition of Oxygen by subtracting the other percentages, since the total must be 100%.
So, the percent composition is 21% N, 6% H, 24% S and 49% O.