12 JSS1
JSS
1504
JSS
14. What fraction of the whole school is
JSS II?
(A) 2 (B) 3 (C)1 (0) 11
20
3
4
4

Which of these will change if the air in aclosed bottle is heated? abcdthe mass of the airthe composition of the airthe air pressure in the bottlethe number of air molecules in the bottle

Ethanol (c2h5oh) is produced from the fermentation of sucrose in the presence of enzymes. c12h22o11(aq) + h2o(g) 4 c2h5oh(l) + 4 co2(g) determine the theoretical yield and the percent yields of ethanol if 680. g sucrose undergoes fermentation and 326.5 g ethanol is obtained. theoretical _ g _ percent %

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.