Answer:
1
only 4 is the significant figure
we take tailing zeroes as significant figures only in case of decimals
The heat released by reaction : C) -8870 J
<h3>Further explanation</h3>
Given
1.008 g of hydrogen
500.00 g water
The temperature rises 25.00 °C to 29.24 °C
Required
energy required
Solution
Q absorbed by water :
Q = m.c.Δt
Q = 500 g x 4.18 J/g C x (29.24-25)
Q = 8870.08 J
The reaction to produce HCl is an exothermic reaction (releasing heat), so that Q is negative
Q water = -Q HCl = -8870.08 J
Single Replacement and Double Replacement reactions