Answer:
31395 J
Explanation:
Given data:
mass of water = 150 g
Initial temperature = 25 °C
Final temperature = 75 °C
Energy absorbed = ?
Solution:
Formula:
q = m . c . ΔT
we know that specific heat of water is 4.186 J/g.°C
ΔT = final temperature - initial temperature
ΔT = 75 °C - 25 °C
ΔT = 50 °C
now we will put the values in formula
q = m . c . ΔT
q = 150 g × 4.186 J/g.°C × 50 °C
q = 31395 J
so, 150 g of water need to absorb 31395 J of energy to raise the temperature from 25°C to 75 °C .
Answer:
False
Explanation:
Half life is the time period at which the concentration of the radioactive substance in decay reduced to half.
<u>Thus, if the hydrogen-3 has gone 2 half lives, it means that it has first reduced to its half and then again the half of what it was, i.e. 1/4</u>
Thus, after two successive half-lives, the concentration must be 1/4 of the initial concentration and hence, the statement is false.
C. The temperature decreases because the most energetic molecules escape.
Answer:
Explanation:
We want the energy required for the transition:
CO 2
(
s
)
+
Δ
→
C
O
2
(
g
)
Explanation:
We assume that the temperature of the gas and the solid are EQUAL.
And thus we simply have to work out the product:
2
×
10^
3
⋅
g
×
196.3
⋅
J
⋅
g
−
1 to get an answer in Joules as required.
What would be the energy change for the reverse transition:
C
O
2
(
g
)
+
→
C
O
2
(
s
)
?
Answer:
ye computer ka sawal he .
