Question

Which of the following is a balanced chemical equation?


Choose one answer.





a. 2 Fe2O3 + 3 C ---> 4 Fe + 3 CO2







b. H2SO4







c. SO2 + O2 + 2 H2O ---> 4







d. H2O2 ---> H2O + O2



.

B?

Answer 1

no. equation means: reaction arrow, and on both sides the same elements in the same amount, with a different arrangement. B) is no reaction

Answer 2

okay the only one i could maybe think of is A

Answer 3

yes. A is balanced. C is rubbish and D is not balanced.

Answer 4

Marks: 1


On AM broadcasts, what remains constant?


Choose one answer.





a. the music







b. the frequency







c. the speech



.

the speech?

Answer 5

frequency.... AM means amplitude modulated... FM would mean frequency modulated.
AM changes the height of the peaks, not the frequency, FM changes the frequency but not the height of the peaks

Answer 6

so its B

Answer 7

?

Answer 8

yes.

Answer 9

Marks: 1


All the different populations that live together in an area make up a/an ______________.


Choose one answer.





a. ecosystem







b. community







c. organism
C?

Answer 10

C?

Answer 11

??

Answer 12

???

Answer 13

?

Answer 14

??

Answer 15

that sounds like B (community) to me.