Answer:
1 girl with long hair she might get it harmed need to be up
2 boy eating in class might be harmful or intoxicated
3 boy playing in back might break a chemical that is harmful
hope this helps
1) Balance of mass
CxHyOz + O2 ---> CO2 + H20
0.880 g + X = 1.760g + 0.720 g
=> X = 1.760g + 0.720g - 0.880g = 1.6 g of O2
2) C in CO2:
molar mass of CO2 = 44 g/mol
=> 12 g C / 44 g CO2 * 1.760 g CO2 = 0.480 g C
3) H in H2O
molar mass of H2O = 18.0 g/mol
2 g H / 18.0 g H2O * 0.720 g H2O = 0.080 g H
4) O
4a) O in CO2: 32gO / 44 g CO2 * 1.760 g CO2 = 1.280 g O
4b) O in H2O: 16gO / 18 gH2O * 0.720 g H2O = 0.640 g O
4c) O in CxHyOz = 1.280 g + 0.64 g - 1.6 g = 0.320 g O
5) Convert grams into moles
C: 0.480 g / 12 g/mol = 0.04 mol
H: 0.08 g / 1 g/mol = 0.08 mol
O: 0.32 g / 16 g/mol = 0.02 mol
6) Divide by the smallest number
C: 0.04 / 0.02 = 2
H: 0.08 / 0.02 = 4
O: 0.02 / 0.02 = 1
7) Use those numbers as subscripts for the empirical formula:
C2 H4 O
Answer: C2H4O
Which formula represents a molecule with the most polar
bond? (1) CO (3) HI (2) NO (4) HCl
The formula that represents a molecule with the most
polar bond is the HCl, hydrochloric acid. The answer is number 4.
The equation is:
Ca(OH)₂(s) + 2 HCl(aq) → CaCl₂(aq) + 2 H₂<span>O(l)
</span>
n=mass in g/M.M
15 g Ca(OH)₂ is n=15 g/ 74.1 g/mol=0.2024 mol of Ca(OH)₂
no. of mol of HCl:
n=0.5 mol/L*0.075L=0.0375 mol
This could react with 0.0375/2= 0.01875 mol of Ca(OH)₂ We have a lot more than that.
Therefore, HCl is the limiting reagent and determines how much CaCl₂ forms.
Based on the balanced reaction, 2 moles of HCl gives 1 mole of CaCl₂
no. of mol of CaCl₂= 0.0375/2= 0.01875 mol
mass in g=n*MM= 0.01875*111= 2.08 g