The three different classes are acidic, basic, or neutral. Ammonia would be basic.
Answer:
The correct answer is B
Explanation:
This question seeks to test the difference between mass and weight.
Mass is a measurement of the amount of matter present in an object. While <u><em>weight is a measurement of the force of gravity pulling (the mass of) an object</em></u>. Hence, measuring the weight of the moon rocks in the moon might be a waste since the weight of the object on earth will produce a different value due to the difference in the force of gravity between the earth and the moon.
Answer:
The final temperature of the water is 25.6 °C.
Explanation:
We have,
Heat added to water is 135.7 J
Mass, m = 54 g
Initial temperature was 25 °C
It is required to find the final temperature of the water. The heat added when temperature is increased is given in terms of specific heat capacity as :
is final temperature
c is specific heat capacity, for water,
So,
So, the final temperature of the water is 25.6 °C.
Answer:
162 kJ
Explanation:
The reaction given by the problem is:
- NBr₃(g) + 3 H₂O(g) → 3 HOBr(g) + NH₃(g) ∆H = +81 kJ
If we turn it around, we have:
- 3 HOBr(g) + NH₃(g) → NBr₃(g) + 3 H₂O(g) ∆H = -81 kJ
If we think now of HOBr and NH₃ as our reactants, then now we need to find out <u>which one will be the </u><em><u>limiting reactant</u></em> when we have 9 moles of HOBr and 2 moles of NH₃:
- When we have 1 mol NH₃, we need 3 mol HOBr. So when we have 2 moles NH₃, we need 6 moles HOBr. We have more than 6 moles HOBr so that's our <em>reactant in excess</em>, thus NH₃ is our limiting reactant.
-81 kJ is our energy change when there's one mol of NH₃ reacting, so we <u>multiply that value by two when there's two moles of NH₃ reacting</u>. The answer is 81*2 = 162 kJ.