CHEM 121 EXAM #1 EXAM WITH CORRECT QUESTIONS AND ANSWERS 2025

CHEM 121 EXAM #1 EXAM WITH
CORRECT QUESTIONS AND ANSWERS
2025

Mixtures:

A) must be heterogeneous

B) must be homogenous

C) always contain only two substances

D) can have variable composition

E) must have a definite composition - CORRECT-ANSWERSAnswer: Can

have a variable composition

most of the elements in the periodic table are classified as:

A) nonmetals

B) metalloids

C) metals

D) allotropes

E) gases - CORRECT-ANSWERSAnswer: metals

how many kg are in 57.0 - CORRECT-ANSWERS5.70 X 10^-8

, which of the following is implicated as the most important gas responsible for

global warming over the past 100 years

A) O2

B) H2O

C) CFC's

D) CH4

E) CO2 - CORRECT-ANSWERSAnswer: CFC's

Alpha Rays are beams of:

A)positively charged particles (helium nuclei)

B) Electrons

C)High energy radiation

D)protons

E) hydrogen stom - CORRECT-ANSWERSAnswer: High energy radiation

which of the following is not an SI base unit:

A) s

B) m

C) K

D) mol

E) g - CORRECT-ANSWERSAnswer: g