9
Explanation:
cause 2 + 2 is equal to 9
D is true because NO2 is a catalyst, and a catalyst is a compound which makes a reaction occur faster (not necessarily more effectively, creating more product, but it decreases the amount of time it takes).
Answer:
How Does a Solar Panel Generate Power? Solar panels use the photons produced by sunlight to generate direct current (DC) electricity. When the photons hit the panel they are absorbed by the panel's semiconducting silicon material.
Explanation:
Answer:
newton's 3 laws state:
- an object in motion stays in motion (unless an external force acts on it)
- every action has an opposite but equal reaction
- force= mass x acceleration
Answer:
The ΔH of the reaction is + 12.45 KJ/mol
Explanation:
Mass of water= 100ml = 100g. (You should always assume 1cm3 of water as 1g)
heat capacity of water = 4.18 Jk-1 Mol-1
Change in temperature = (19.86 - 25.00) = -5.14 K (This is an endothermic reaction because of the fall in temperature)
Molar mass of NaHCO3 = 84 g/mol
Mole of NaHCO3 = 14.5 / 84 = 0.173 mol
Step 1 : Calculate the heat energy (Q) lost by the water.
Q = M x C x ΔT
Q = -100 x 4.18 x (-5.14)
Q = 2148.5 joules
Q = 2.1485 K J
Step 2: Calculating the ΔH of the reaction?
ΔH = Q / number of moles of NaHCO3
ΔH = 2.1485 / 0.173
ΔH = 12.42 KJ/mol
