Answer:
13) Carbon Dioxide and water
Explanation:
The fact is that during photosynthesis, Carbon Dioxide is needed by green plants to manufacture their food and water is also needed but also chloroplast which contained chlorophyll is also needed
hence, the options are somehow confusing
14) perhaps it should be all of the above
Answer : The energy gained by copper can be calculated by using the below formula :
Energy = Mass X Specific heat X Temperature change.
Solution : Given, Mass of Cu = 48.7
Specific heat = 0.385
Temperature change = 10 to x = (x-10)
On substituting the values we get,
Energy = 48.7 X 0.385 X (x-10) = 18.7495 X (x-10) KJ
Answer:
Longer hydrocarbon molecules have a stronger intermolecular force. More energy is needed to move them apart so they have higher boiling points . This makes them less volatile and therefore less flammable
Answer:
4.D. 2KJ
5.B. close to 0 degree celsius
Explanation:
heat absorbed= heat given out
100g * 4.2 * (x-0)= 400g * 4.2* ( 20-x) where x is the new temp reached
then x= 20
i.e. the temperature of ice increases to 5 degree celsius and the temperature of water decreases to 5 degree celsius .
hope it helps