Answer:
The enthalpy change per mole of sodium when sodium reacts with water is 28.36 kJ
Step-by-step explanation:
The given parameters are;
Mass of sodium = 8 grams = 0.008 kg
Volume of water = 227 cm³ = 0.000227 m³
Initial water temperature, T₁ = 298 K
Final water temperature, T₂ = 308.4 K
Specific heat capacity of water = 4.18 J/(K·g)
Density of water = 1000 kg/m³
Mass of water = 1000×0.000227 = 0.227 kg = 227 g
Heat change, ΔH = m×c×ΔT = m×c×(T₂ - T₁)
ΔH = 227*4.18*(308.4 - 298) = 9868.144 J = 9.868 kJ
Molar mass of sodium = 22.989769 g/mol
Therefore, 8 grams contains;
8/22.989769 = 0.348 moles of Na
Which gives the enthalpy change per 0.348 moles of Na when sodium reacts with water = 9.868 kJ
Therefore, when one mole of Na reacts with water we have;
The enthalpy change per 0.348/0.348 = 1 mole of Na when sodium reacts with water = 9.868 kJ/0.348 = 28,358.3 J = 28.36 kJ.
Answer:
y < -2x - 4
Step-by-step explanation:
This is a guessing game. You just have to plug and chugg to find your answer.
Look at the table they gave you and plug in the x and y value into the given equations and see if they're true or not.
For example, I used the point x=-2 and y=1 from the table.
I plug that into y < -2x - 4 and got a false statement:
y < -2x - 4
(1) < -2(-2) - 4
1 < 4 - 4
1 < 0
this is false because one cannot be less than zero. Therefore this equation is the wrong one.
If you tried to plug in x=-2 and y=1 into the other 3 equations you'll see that they'll be correct.
Answer: 13 uniforms.
Step-by-step explanation: To solve the given problem we need to calculate the number of basketball uniforms that were purchased if the cost of each uniform was $60, using the given equation:
C=
substituting C=60:
multiplying both sides by n:
60n=40n+260
60n-40n=260
20n=260
n=260/20
n=13.
13 uniforms were purchased.