Chose 2 boxes
a) a gas is given off. (b) a colour change. (c) a temperature rise. (d) a new substance forms. (e) an energy change occurs.
What always happens in a chemical reaction?
2010-06-13 1:51 pm
回答 (4)
2010-06-13 2:02 pm
✔ 最佳答案
(d) a new substance forms. (e) an energy change occurs.
The reason is because there is bond breaking and bond forming taking place, so new substances must be made and there will be and energy change (either temperature rise or fall).
2010-06-13 2:09 pm
I think the answer is d)....
for e). Although i think 99.999%of chemical reaction involve an energy change. But i think that in theory, if the stability of the product and reactant remain the same. The enthalphy change can equal to zero.
for e). Although i think 99.999%of chemical reaction involve an energy change. But i think that in theory, if the stability of the product and reactant remain the same. The enthalphy change can equal to zero.
2015-08-07 6:04 am
This Site Might Help You.
RE:
What always happens in a chemical reaction?
Chose 2 boxes
a) a gas is given off. (b) a colour change. (c) a temperature rise. (d) a new substance forms. (e) an energy change occurs.
RE:
What always happens in a chemical reaction?
Chose 2 boxes
a) a gas is given off. (b) a colour change. (c) a temperature rise. (d) a new substance forms. (e) an energy change occurs.
參考: chemical reaction: https://tr.im/OdjwR
2010-06-14 3:15 pm
d) a new substance forms; this is only option which always accompanies a chemical reaction.
a gas may or may not be formed ,a color change may or may not occur,temperature may rise or fall,energy change may be due to change in physical state.
a gas may or may not be formed ,a color change may or may not occur,temperature may rise or fall,energy change may be due to change in physical state.
2010-06-13 1:56 pm
d and e
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