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
The name is Potassium bromide.
Answer:
1= Magnesium
2 = Option 3 = 1s² 2s² 2p⁶
Explanation:
An electrically neutral atom consist of equal number of protons and electrons.
The answer for 1st q is magnesium because the electronic configuration showed twelve number of electrons. The atomic number of magnesium is twelve that's why this configuration is of Mg.
Mg₁₂ = 1s² 2s² 2p⁶ 3s²
The second answer is option three because has atomic number ten and third electronic configuration have ten electrons.
Ne₁₀ = 1s² 2s² 2p⁶
It is stable electronic configuration. Neon is inert because of this electronic configuration. The outer most shell is completely filled.
Answer:
O Option 1
Explanation:
IF ENERGY IS RELEASED, THEN ENERGY RELEASED SHOULD BE SUBTRACTED FROM ORIGINAL.
(16.32 X 10^-19) - (5.4 X 10^-19)
10.92 X 10^-19
X:5.8g=16:(23+1+12+3*16)
x:5.=16:84
x:=5.8* 16/84
this is approximately 1.1
