Science Assessment ~ Topics ~ Substances, Chemical Reactions, and Conservation of Matter ~ Item SC078003 ~ Student Performance

A student uses a knife to cut a stick of butter on a dish into smaller pieces. The student weighs the dish, knife, wrapper, and butter before and after cutting the butter into pieces.

Will the dish, knife, wrapper, and butter weigh more, less, or the same when the butter is in small pieces and why?

They will weigh more because there are more pieces of butter.
They will weigh less because the butter is in smaller pieces.
They will weigh less because some of the butter disappears when it is cut.
They will weigh the same because the amount of butter has not changed.

Distribution of responses
Answer Choice		Overall	Grades		Gender		Primary Language
		n = 3664	6–8 n = 2440	9–12 n = 1216	Male n = 1762	Female n = 1828	English n = 3209	Other n = 377
A.	They will weigh more because there are more pieces of butter.	8%	7%	8%	8%	7%	7%	12%
B.	They will weigh less because the butter is in smaller pieces.	11%	13%	9%	12%	11%	12%	11%
C.	They will weigh less because some of the butter disappears when it is cut.	10%	10%	10%	12%	8%	10%	14%
D.	They will weigh the same because the amount of butter has not changed.	71%	70%	73%	68%	74%	72%	63%

Science Assessment

Item SC078003: Mass is conserved when a stick of butter is cut into pieces.