If a sample of matter cannot be separated by physical means, what can be said with certainty about that sample?

A It is a pure substance.

B It is an element.

C It is a compound.

D It is a mixture.

Identify which one of these are exact numbers. (Can be more than 1) a. 2.54 cm (the number of centimeters in exactly 1 in) b. 56.00 s (a time measured by a stopwatch) c. 4 choices (the number of choices in this list) d.

The process by which an animal becomes accustomed to its situation is referred to as A. Habituation B nurturing C aggression D desensitizating

The closeness or reproducibility of a set of measurements taken under the same conditions is known as which of the following? Accuracy Significant Figures Absolute figures Precision

The planet mars has two moons, deimos and phobos. phobos is about 9,000 km from mars and is about six times more massive than deimos. deimos is about 23,000 km from mars. upon which moon does mars exert a stronger gravitational force?

Hess's law is based on what principal?

Read the scientific question below. "Does sunlight make plants live?" What is a likely hypothesis for the question?

A chemist is using a solution of HNO3 that has a pH of 3.75. What is [H+] for the solution?

What is the oxidation number for CO2

Which is a property of acids in aqueous solutions?

On the periodic table, calcium and bromine are located in period 4. What is one difference between the two elements? A. Calcium atoms are more reactive than bromine atoms. B.