Q: Chemical and physical changes in a system may be accompanied by an increase or a decrease in the disorder of the system, corresponding to an increase or decrease in what? Choices: - enthalpy - vibration - volume - entropy A:
entropy

(Question)
Q: The mean free path for a gaseous molecule will be hundreds of times the what of the molecule? Choices: - variation - weight - density - diameter A:
(Answer)
diameter

Ques: Q: In their pure form, all elements have an oxidation number of what? Choices: - 3 - 2 - 7 - zero A:
Ans: zero

(Q).
Q: Steam consists of what common and essential element in its gaseous phase? Choices: - carbon dioxide - air - plasma - water A:
(A).
water

Ques:Q: To undo the tarnish on copper pennies, you can place them in what liquid? Choices: - distilled water - honey - seawater - vinegar A:

Ans:vinegar

Ques: Q: How does litmus paper indicate the ph value of a solution? Choices: - by texture - by shape - by smell - by color A:
Ans:
by color