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2 years ago

Can someone please help me with these three questions, it will soon be due.

Chemistry

1 answer:

Mice21 [21]2 years ago

8 0

YOU also better mark me BRAINLIEST if someone else answers!!!

volume = 100 mL

density = 1.02 g / mL

mass = density x volume

= 1.02 x 100
= 102 g

Cp = 4.03 J / oc g
dT = 28.7 - 23.5 = 5.2 oC
Q = m Cp dT
Q = 102 x 4.03 x 5.2
Q = 2138 J
Q = 2.14 kJ

heat absorbed = 2.14 kJ

We can calculate the moles of HC1 present in 50 ml 1m solution by using the formula, moles = volume of solution in L*molarity
moles = 50/1000 = .05 , L*1 M = .05 Moles of HCL.
The same can be applied for calculation of moles fo Na OH of 50 ml, 1 M solution. (50 ml NaOH = .o5 L NaOH)
Then use the formula = volume of solution / 1000*moles.wt,
=1.825 gram.
moles=mass in grams /moles.wt= .05 moles of HCI
calculate moles of water from this reaction.
HC1+NaOH----->NACl+h20 (Balanced Equation)
.5+.5----> .5+.5
.05 moles of water
Delta H=q/n.
n=.05 to calculate the Delat H.

3) I don't understand it, sorry

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