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2 years ago

SOMEONE PLEASE HELP

Chemistry

1 answer:

Snowcat [4.5K]2 years ago

6 0

Answer:

a. release of heat flames or light - Physical Change

b. formation of precipitate - Chemical Change

c. change in substances size - Physical Change

d. change in an objects shape - Physical Change

e. change in an objects phase of matter - Physical Change

f. releasing gases/bubbles - Chemical Change

Explanation:

These are all either changes in physicality or in chemical structures; hope I helped either way!

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$q=m\times c\times (T_{final}-T_{initial})$

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q = heat absorbed = ?

$c$ = specific heat of water = $4.18J/g^oC$

m = mass of water = 100 g

$T_{final}$ = final temperature of water = $27.5^0C$

$T_{initial}$ = initial temperature of metal = $21.0^0C$

Now put all the given values in the above formula, we get:

$q=100g\times 4.18J/g^oC\times (27.5-21.0)^0C$

$q=2719.6J=2.72kJ$

Thus, the heat released during the neutralization = 2.72 KJ

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0.05 moles of $HCl$ releases heat = 2.72 KJ

1 mole of $HCl$ releases heat = $\frac{2.72}{0.05}\times 1=54.4KJ$

Thus the enthalpy change for the reaction in kJ per mol of HCl is 54.4 kJ

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