To convert Celsius to kelvin, we need to know the formula. Kelvin = Celsius + 273.15. Now, we can figure out how many degrees kelvin -12 degrees Celsius is.
Kelvin = -12 + 273.15
Kelvin = 261.15
Question #1
Potasium hydroxide (known)
volume used is 25 ml
Molarity (concentration) = 0.150 M
Moles of KOH used
0.150 × 25/1000 = 0.00375 moles
Sulfuric acid (H2SO4)
volume used = 15.0 ml
unknown concentration
The equation for the reaction is
2KOH (aq)+ H2SO4(aq) = K2SO4(aq) + 2H2O(l)
Thus, the Mole ratio of KOH to H2SO4 is 2:1
Therefore, moles of H2SO4 used will be;
0.00375 × 1/2 = 0.001875 moles
Acid (sulfuric acid) concentration
0.001875 moles × 1000/15
= 0.125 M
Question #2
Hydrogen bromide (acid)
Volume used = 30 ml
Concentration is 0.250 M
Moles of HBr used;
0.25 × 30/1000
= 0.0075 moles
Sodium Hydroxide (base)
Volume used 20 ml
Concentration (unknown)
The equation for the reaction is
NaOH + HBr = NaBr + H2O
The mole ratio of NaOH : HBr is 1 : 1
Therefore, moles of NaOH used;
= 0.0075 moles
NaOH concentration will be
= 0.0075 moles × 1000/20
= 0.375 M
Chemical would be the correct answer
False, a gas that produces a pop is hydrogen
Hope this helped :)
Answer:
Alright, the first thing we have to do is to balance the chemical equation
2Na3N -----> 6Na + 1N2
We have 60g of Na3N, we convert them into moles by dividing the mass of the compound by the molar mass.
Molar mass of Na3N = (22.98 x 3) + (14) = 82.94g/mol
<u>60</u> = 0.72341451651 moles of Na3N
82.94
Now because we did the balanced equation, we know the mole to mole ratio of Na3N to N2 would be 2:1, so in order to get the moles of N2 you have to divide the moles of Na3N by 2
0.72341451651 moles/2 = 0.361707258 moles of N2
Now that we have the moles of N2, we just have to determine the mass of it in grams. In order to do that, just multiply the moles by the molar mass of N2 (28g/mol)
0.361707258 x 28 = <u>10.13g of N2</u>
<u>Therefore the decomposition of 60g of Na3N would result in 10.13g of N2 (nitrogen gas)</u>
