potential energy because it has a potential to roll down the hill, creating kinetic energy. it is idle
Answer:
Explanation:
Molarity is a measure of concentration in moles per liter.
There are 0.250 moles of sodium hydroxide (NaOH) and 500 milliliters of water. We need to convert milliliters to liters. Remember that 1 liter contains 1000 milliliters.
Now we have the values to solve for molarity:
- moles= 0.250 mol NaOH
- liters= 0.5 L
Substitute the values into the formula.
Divide.
- 1 mole per liter (mol/liter) is equal to 1 Molar or M.
- Our answer of 0.5 moles of sodium hydroxide per liter is equal to 0.5 M NaOH
The molarity of the solution is <u>0.5 M NaOH</u>
Answer:
w/v% = gm per 100 ml
75gm X gm 7500
------- = ------ == --------
1500ml 100ml 1500X
X=5%
Firstly, next time you post questions, I suggest you split the questions up so the format is easier to read.
Question 4:
If you use Hess's Law. you subtract the enthalpy of formation of the reactants from the enthalpy of formation of the products. Therefore, Question 4 is "The enthalpy of formation reactions."
Question 5:
Reactions that release heat have a negative enthalpy overall. Therefore, Question 5 is:
<span>PCl3(l) + 1/2 O2(g) → POCl3(l) ΔH = -325.7 kJ
PCl3(g) + Cl2(g) → PCl5(g) ΔH = -92.5 kJ
Question 6:
As said in Question 4, you subtract the enthalpies of formation of the reactants. Therefore, Question 6 is </span><span>N2 (g) and H2 (g).
Question 7:
Balancing the equation, we get:
2 NO2 --> O2 + 2NO
Now using Hess's Law to calculate enthalpy:
(0.0 + 2(90.37))-2(33.85)
=113.0 (Rounding using sig figs)
Therefore, Question 7 is 113.0 kJ.
Question 8:
If you are multiplying by one, you aren't changing anything; therefore, Question 8 is "It must be left alone."</span>
