Answer:
elements are composed of
electrons with a little mass and negative charge
protons with mass and positive charge
neutrons with mass and no charge
isotopes same number of protons, different in neutrons
share me the other part of the photo to complete!!!
Density is defined as the ratio of mass to the volume.
Density = 
(1)
Mass of water = 10 grams
Mass of acetone = 10 grams
Density of water = 1 
Density of acetone = 0.7857
Put the value of density of water and its mass in equation (1)
1 = 
Volume of water = 10 
Put the value of density of acetone and its mass in equation (1)
0.7857 =
Volume of acetone = 12.72
Thus, volume of acetone is more than volume of water because the density of acetone is lower.
The paper is not clear so please ask your problem again with more clear print
Answer:
= -356KJ
<em>therefore, the reaction where heat is released is exothermic reaction since theΔH is negative</em>
Explanation:
given that enthalpy of gaseous reactants decreases by 162KJ and workdone is -194KJ
then,
change in enthalpy (ΔH) = -162( released energy)
work(w) = -194KJ
change in enthalpy is said to be negative if the heat is evolved during the reaction while heat change(ΔH) is said to be positive if the heat required for the reaction occurs.
At constant pressure the change in enthalpy is given as
ΔH = ΔU + PΔV
ΔU = change in energy
ΔV = change in volume
P = pressure
w = -pΔV
therefore,
ΔH = ΔU -W
to evaluate energy change we have,
ΔU =ΔH + W
ΔU = -162+ (-194KJ)
= -356KJ
<em>therefore, the reaction where heat is released is exothermic reaction since theΔH is negative</em>
