First, we have to get:
1- The heat required to increase T of ice from -50 to 0 °C:
according to q formula:
q1 = m*C*ΔT
when m is the mass of ice = mol * molar mass
= 1 mol * 18 mol/g
= 18 g
and C is the specific heat capacity of ice = 2.09 J/g-K
and ΔT change in temperature = 0- (-50) = 50°C
by substitution:
∴q1 = 18 g * 2.09 J/g-K *50°C
= 1881 J = 1.881 KJ
2- the heat required to melt this mass of ice is :
q2 = n*ΔHfus
when n is the number of moles of ice = 1 mol
and ΔHfus = 6.01 KJ/mol
by substitution:
q2 = 1 mol * 6.01 KJ/mol
= 6.01 KJ
3- the heat required to increase the water temperature from 0°C to 60 °C is:
q3 = m*C*ΔT
when m is the mass of water = 18 g
C is the specific heat capacity of water = 4.18 J/g-K
ΔT is the change of Temperature of water = 60°C - 0°C = 60°C
by substitution:
∴q3 = 18 g * 4.18 J/g-K * 60°C
= 4514 J = 4.514 KJ
∴the total change of enthalpy = q1+q2+q3
= 1.881 KJ +6.01 KJ + 4.514 KJ
= 12.405 KJ
Answer:
0.2 mL stock solution, 0.8 solvent, 0.1 mL first solution and 0.9 solvent
Explanation:
The final volume for fist solution is 1 mL and concentration must will be 1/5, then 1 mL/5=0.2 mL. For complete the 1 mL add the missing solvent volume 1 mL-0.2 mL=0.8 mL. For second solution, assuming final volume is 1 mL, and concentration 1/10, then we have 1 mL /10=0.1 mL solution 1/5. Completing volume, 1 mL-0.1 mL= 0.9 mL solvent.
To determine molecular formula, we first need to find out its empirical formula,
Carbon. Hydrogen. Nitrogen. Oxygen
Mass. 49.98g. 5.19g. 28.85g. 16.48g
Mole. 4.165. 5.19. 2.06. 1.03
Divide 4. 5. 2. 1
by
smallest
So by comparing the mole ratio from the table above, i hope u understand the table
The empirical formula is C4H5N2O
given molecular mass = 194.19g
so
(C4H5N2O) n= 194.19
(48+5+28+16)n=194.19
n= 2
molecular formula = C8H10N4O2
Answer:
I would love to say C but I know me so A
Hey there!!
A lawn mower works by converting chemical energy (energy stored in the gas) to mechanical energy.
Hope this helps you and have a great day!!!! I wish you the best of luck (:
