Answer 1:
Correct Answer: Option A i.e. <span>The temperature stays constant for a while, then rises (A).
Reason:
At 0 oC, H2O exist in dual state (solid and liquid) i.e. there exist an equilibrium between ice and water. Hence, when the heat is supplied, it is initially used to bring about phase transformation from solid to liquid state. During this time, temperature remains constant. Once the phase transformation has occurred, heat is utilized for increasing the temperature of system i.e. water.
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Answer 2:
Correct Answer: Option </span><span>B) At first, the energy supplied goes into overcoming attractive forces in the solid. </span><span>
Reason:
In the present case, initially</span> the energy supplied goes into overcoming attractive forces in the solid. Once the ice is converted into water, it now exist in single phase i.e .liquid. Hence, now when further heat is supplied to the system, it is used only for increasing the temperature of system.
Answer:
B) Co2 cuz in the diagram I see two similar atoms it might be of (oxygen) and the one atom of (carbon)
Answer:
4 g after 58.2 years
0.0156 After 291 years
Explanation:
Given data:
Half-life of strontium-90 = 29.1 years
Initially present: 16g
mass present after 58.2 years =?
Mass present after 291 years =?
Solution:
Formula:
how much mass remains =1/ 2n (original mass) ……… (1)
Where “n” is the number of half lives
to find n
For 58.2 years
n = 58.2 years /29.1 years
n= 2
or 291 years
n = 291 years /29.1 years
n= 10
Put values in equation (1)
Mass after 58.2 years
mass remains =1/ 22 (16g)
mass remains =1/ 4 (16g)
mass remains = 4g
Mass after 58.2 years
mass remains =1/ 210 (16g)
mass remains =1/ 1024 (16g)
mass remains = 0.0156g
Answer:
118 elements
Explanation:
Of these 118 elements, 94 occur naturally on Earth.
