Democritus believed that the universe was composed of atoms, correctly, of course. However, at the time, Plato's and Aristotle's hypothesi were just as valid because everyone was a philosopher. There were no scientists back then.
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
Answer:
a straight neck flask to allow air to get in
Explanation:
I took the test eWe
Answer:
#1 is protons electrons and neutrons
their respective parts are center, positive ,and no charge
#2 is positive charge, chemical properties
#3 is the number of protons, characteristics, same
#4 is atomic mass, average atomic mass
#5 is mass number, nucleus
Explanation:
no need to say thank tou i know ur in class
Answer:
Explanation:
mass of the reactant = mass of the product
15.31 + 1.50 = 16.81g
