Heat gained by ice cubes would be equal to the - heat lost by warm water
The moles of ice is: 50.5 g / 18.0 g/mol = 2.81 mol
Heat required to melt all of the ice is equal to: 2.81 mol X 6.02 kJ/mol = 16.9 kJ = 16890 J
Now, know whether the warm water will still be above 0C when it loses this much heat:
-1690 J = 160 g (4.184 J/gC) (Delta T) Delta T = -25C
In order to solve for the final temperature, going back to include warming of the melted ice to a final temperature:
q(ice/water) = - q(warm water)
moles (Delta Hf) + m c (T2-T1) = - m c (T2-T1)
50.5 g / 18.0 g/mol = 2.81 mol
2.81 mol X 6.02 kJ/mol + 50.5g (4.184 J/gC) (T2-0) = -160g (4.184 J/gC) ( T2-80)
16916 + 211.3T2 = -669.4 T2 + 53555
36639 = 880.7 T2
T2 = 41.6 C
Answer : 21.12 g
explanation :
- A limiting reactant is the substance that is totally consumed when the chemical reaction is complete and the reaction cannot continue without it.
- This is a limiting reactant problem because the amount of product (CO2) formed is limited by this substance (either O2 or C3H8).
- We can predict the limiting reactant by calculating number of mole for all reactants;
n (C3H8) = mass/ molar mass = 7/[(12 × 3)+(1 ×8)] = 0.16 mol
n (O2) = mass/ molar mass = 98/(16 × 2) = 3 mol
But we know from this balanced equation that for the reaction to continue, for (n) of propane there must be (5n) of oxygen. Clearly we have more oxygen than required for the reaction to continue as
[ 3 O2 mol > (0.16 propane mol × 5) . Hence, the limiting reactant is propane.
- Using cross multiplication,
0.16 mol propane → 1 mol propane
? → 3 mol CO2
So (n) of CO2 produced = 0.16 × 3 / 1 = 0.48 mol ,
And mass of CO2 produced = n × molar mass = 0.48 × [12 + (16 ×2)] = 21.12 g..
1) Atomic number of magnesium (Mg) is 12, it means that it has 12 protons and 12 electrons.
Electron configuration of magnesium atom: ₁₂Mg 1s² 2s² 2p⁶ 3s².
2) Atomic number of aluminium (Al) is 13, it means that it has 13 protons and 13 electrons., but if it lost one electron, it will have 12 electrons and 13 protons and become aluminium cation Al⁺.
Electron configuration of aluminium cation: ₁₃Al⁺ 1s² 2s² 2p⁶ 3s².
3) Atomic number of silicon (Si) is 14, it means that it has 14 protons and 14 electrons., but if it lost two electrons, it will have 12 electrons and 14 protons and become silicon cation Si²⁺.
Electron configuration of silicon cation: ₁₄Si²⁺ 1s² 2s² 2p⁶ 3s².
Given:
0.103 grams of Zinc (solid)
50 ml of HCl
Density of HCl = 1.0 g/mL
Initial Temperature (Ti) = 22.5 C
Final Temperature (Tf) = 23.7 C
Solve for the mass of HCl:
50 mL * 1.0 g/mL = 50 g
Assume that the Cp for HCl is similar to the Cp of water:
q = mCpdT
= mCp (Tf - Ti)
= 50 g * 4.18 J/gC * (23.7 - 22.5)
q = 250.8 J = H
Answer:
The mole and atonmicity of both the gases are different, the number of atoms is not same.
Explanation:
The number of atoms in a molecule (compound) depends on mole number and atomicity.
↬ Mole of 100 g H₂ = 100g ÷ 2u = 50 mole
∴Number of atoms in 100 g H₂
= 2 x 50 x 6.022 × 10²³
= 6.022 x 10²⁴ atoms
↬ Mole of 100 g He = 100g ÷ 4u = 25 mole
∴ Number of atoms in 100 g He
= 1 × 25 × 6.022 × 10²³
= 150.55 × 10²³
= 1.5055 x 10²⁵ atoms
Thus, The mole and atonmicity of both the gases are different, the number of atoms is not same.
<u>-TheUnknownScientist</u><u> 72</u>
