Answer:
V = 4/3 * 3.1416 * (37x10-10)3
V = 2.12x10-25 cm3
d = m/V
d = 1.67x10-24 / 2.12x10-25 = 7.87 g/cm3
The difference in temperature, let's convert F to ºC:
ºC = -80-32/1.8 = -62.22 ºC
dT = -92.6 + 62.2 = -30.4 ºC
Answer:
Explanation:
Given parameters:
Mass of aluminium oxide = 3.87g
Mass of water = 5.67g
Unknown:
Limiting reactant = ?
Solution:
The limiting reactant is the reactant in short supply in a chemical reaction. We need to first write the chemical equation and convert the masses given to the number of moles.
Using the number of moles, we can ascertain the limiting reactants;
Al₂O₃ + 3H₂O → 2Al(OH)₃
Number of moles;
Number of moles =
molar mass of Al₂O₃ = (2x27) + 3(16) = 102g/mole
number of moles = = 0.04mole
molar mass of H₂O = 2(1) + 16 = 18g/mole
number of moles = = 0.32mole
From the reaction equation;
1 mole of Al₂O₃ reacted with 3 moles of H₂O
0.04 mole of Al₂O₃ will react with 3 x 0.04 mole = 0.12 mole of H₂O
But we were given 0.32 mole of H₂O and this is in excess of amount required.
This shows that Al₂O₃ is the limiting reactant
Answer:
Empirical CHO2
Molecular C2H2O4
Explanation:
To determine the formulas, firstly, we need to divide the percentage compositions by the atomic masses.
Kindly note that the atomic mass of carbon, oxygen and hydrogen are 12, 16 and 1 respectively. We proceed with the division as follows:
C = 26.7/12 = 2.225
H = 2.2/1 = 2.2
O = 71.1/16 = 4.44375
We then proceed to divide by the smallest value which is 2.2 in this case
C = 2.25/2.2 = 1
H = 2.2/2.2 = 1
O = 4.44375/2.2 = 2
Thus, the empirical formula is CHO2
We now proceed to get the molecular formula as follows
[12+ 1 + 16(2) ]n = 90.04
45n = 90.04
n = 90.04/45 = 2
The molecular formula is :
C2H2O4
It will slowly rotten and turn brown
The minimum volume of 0.2M sodium sulfide that will precipitate out aluminum from 50.0 mL, 0.25 M aluminum nitrate would be 0.094 L or 94 mL
<h3>Stoichiometric calculation</h3>
From the equation of the reaction:
Mole ratio of Na2S and Al(NO3)3 = 3:2
Mole of 50.0 mL, 0.25 M Al(NO3)3 = 50/1000 x 0.25
= 0.0125 mole
Equivalent mole of Na2S = 3/2 x 0.0125
= 0.0188 mole
Volume of 0.2M, 0.0188 mole Na2S = 0.0188/0.2
= 0.094 L or 94 mL
More on stoichiometric calculations can be found here: brainly.com/question/8062886