Answer:
m = 2 g
Explanation:
Given data:
Initial temperature = 45°C
Final temperature = 35°C
Heat evolved = 84 j
Mass of water = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
specific heat capacity of water is 4.18 J/g.°C
ΔT = 35°C - 45°C
ΔT = - 10°C
84 j = m ×4.18 J/g.°C ×- 10°C
84 j = m × -41.8 J/g
m = 84 j / -41.8 J/g
m = 2 g
negative sign shows heat is evolved.
Competition is most likely to occur between two organisms. When the organisms interfere with each others resource or when organisms interfere with each others reproduction which will cause the others life to be in short or danger.
The theoretical yield and percent yield of hydrogen if 0.27 g of H2 collected is calculated as follows
write the reaction equation
that is Fe + Hcl = H2 + FeCl2
calculate moles of Fe = mass/molar mass = 8.85 g/56 g/mol =0.158 moles
by use mole ratio between Fe : H2 which is 1:1 the theoretical moles of hydrogen = 0.158moles
the theoretical mass is therefore = moles x molar mass
= 0.158 mol x2g/mol =0.316 grams
% mass = actual mass/ theoretical mass x 100
= 0.27/0.316 x100 = 85.4 %
The answer is P
You can count how many electrons in the picture
Or you can search for the one who has 3 electrons in the outer shell
