Question

Giselle is working with a chemical substance in a laboratory. She observes that when the chemical is heated, it gives off a gas. She assumes that the gas is oxygen but decides to test this assumption to verify it. Which type of scientific knowledge is Giselle’s assumption?

A.
fact
B.
hypothesis
C.
law
D.
observation
E.
theory

Answer 1

Giselle's assumption about the gas being oxygen is a hypothesis, which is an educated guess or prediction that can be tested through experiments or further observation.

Step-by-step explanation:

Giselle's assumption that the gas given off when the chemical is heated is oxygen can be classified as a hypothesis. A hypothesis is a tentative explanation for an observation or phenomenon, based on available scientific knowledge. It is a prediction or educated guess that is testable and falsifiable through controlled experiments or additional observation. In science, it is a step that precedes the development of a theory or a law, and it must be possible to design an experiment to test this hypothesis. For Giselle, she could test the presence of oxygen by examining whether the gas supports combustion, which is a characteristic property of oxygen.

Answer 2

Giselle's assumption about the gas being oxygen when a chemical is heated is a hypothesis. A hypothesis is a testable tentative explanation based on scientific observation. The correct option is B. hypothesis.

Step-by-step explanation:

Giselle’s assumption that the gas given off when a chemical is heated is oxygen is best described as a hypothesis. A hypothesis is a tentative explanation for a scientific observation that can be tested through experimentation or further observation. It is grounded in scientific knowledge, must be logical, and should be able to be proven false if it is indeed not correct. Since Giselle's assumption is based on prior observations and is testable, it fits the definition of a hypothesis.

In this scenario, Giselle could design an experiment to test her hypothesis by collecting the gas and then applying a glowing splint to see if the gas relights it, which is a common test for the presence of oxygen.