In an experiment, seth was given a substance known as ammonium carbonate, (nh4)2co3. seth connected a bunsen burner to the gas valve using a gas hose. he turned on the gas valve and lit the bunsen burner. using a test tube, seth heated a piece of ammonium carbonate. seth noticed the following:
- condensation appeared on the sides at the top of the test tube.
- an ammonia smell was coming from the test tube.
seth continued to light a wooden splint and stick it down the test tube and it immediately was extinguished.

throughout this experiment, how many signs of chemical changes were observed and actual chemical changes took place?
a) 4
b) 5
c) 6
d) 7

B

Step-by-step explanation: do you still need help with this let me know :P

=====================================

explanation

the graph has a slope of 1/3 because each time you move up 1, you go to the right 3. so, slope = rise/run = 1/3. we can cross choice a off the list since we want a slope of 3, rather than 1/3.

the first table shown has a slope of -3. this is because the rise is -6 and the run is 2, so slope = rise/run = -6/2 = -3. note how x increases by 2 each time (run) and y drops by 6 each time (rise). choice b can be eliminated.

the second table has a slope of 3. each time x goes up by 1, the y values increase by 3. slope = rise/run = 3/1 = 3. alternatively you can use the slope formula to prove that the slope is 3 here. use any two rows of values to generate the two points. choice c is one of the answers

the third table also has a slope of 3. let's use the slope formula to prove as such. i'm going to use the first two rows of the table. so i'll use the two points (2,1) and (5,10)

m = slope

m = (y2-y1)/(x2-x1)

m = (10-1)/(5-2)

m = 9/3

m = 3 so we get a slope of 3

choice d is the other answer