Answer:
4 significant figures
Explanation:
505 has 3 significant figures
450.25 has 5 significant figures
First do simple subtraction
505 - 450.25 =54.75
And then evaluate any number that has significance or is important if the decimal were to be moved.
4 significant figures
Answer:
1.11 M
Explanation:
Please refer to the attachment
2H2 + O2 ---->2H2O
number of moles in reaction 2 mol 1 mol 2 mol
number of liters in the reaction 2*22.4 L 1*22.4 L 2*22.4L
We can see that volumes of the gases are proportional to coefficients in the reaction ( if gases are under the same conditions), so we can write
2H2 + O2 ---->2H2O
2 L 1 L 2 L
given 40 L ( 25 L) 40 L
We can see that we have excess of O2,
because if 2 L H2 are needed 1 L O2, then 40 L of H2 are needed 20 L O2.
So, limiting reactant is H2, and we will need to calculate Volume of H2O using H2.
2L H2 give 2L H2O(gas), so 40 L H2 give 40 L H2O.
Al₂O has a higher percentage of aluminium.
Explanation:
To solve this problem, we have to compare the molar mass of the aluminium in each compound to one another as percentage of the whole compound:
Molar mass of Al₂O = 2(27) + 16 = 70g/mol
Molar mass of Al(NO₃)₃ = 27 + 3[14 + 3(16)] = 213g/mol
Percentage by mass of Al in Al₂O =
x 100 = 77%
Percentage by mass of Al in Al(NO₃)₃ =
x 100 = 12.7%
Al₂O has a higher percentage of aluminium.
learn more:
Molar mass brainly.com/question/2861244
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You would get 35.................