CHM110FA25 Exam 1 Review

An example of a physical property is ___

• flammability

• ability to rust

• color

• acidity

Which of the following are chemical changes?

• Fog forms from water vapor when the temperature dips below the dew point

• Decomposition of oil in a landfill produces methane (natural gas)

• Oxygen (O2) is converted to ozone (O3) during a thunderstorm

• Yeast use fermentation to convert glucose to ethanol.

Which of the following is an ionic compound containing an anion with -1 charge?

• H₂O

• KCl

• CO₂

• MgO

C is a(n) ____ and CH4 is a(n)

•  molecular element; molecular compound

•  molecular element; molecular element

• atomic element; molecular compound

•  atomic element; molecular element

Tags

NGSS.MS-PS1-1

Determine the empirical formula for the compound with the following percent compositions:

 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen

A compound of carbon and hydrogen contains 92.3% C and has a molar mass of 78.1 g/mol. What is its molecular formula?

A fictitious element X has three naturally-occurring isotopes: 33.99 amu, 63.50 % ; 34.99 amu, 10.50 % ; 35.98 amu, 26.00 % What is the average atomic mass of element X?

• 11.53 amu  

• 33.99 amu     

• 34.61 amu

•  35.98 amu

A scientist made an observation and came up with a possible explanation for it.  The possible explanation was tested many times in many ways. The results of the tests supported the validity of the explanation.  At this point, the explanation should be referred to as:

• law

• hypothesis

• theory

• phenomenon

Tags

NGSS.HS-PS1-2

A glass of orange juice with pulp is a ____ mixture; A beaker containing a sugar solution is a ____ mixture

• homogeneous, homogenous

• heterogeneous, heterogenous

• homogenous, heterogeneous

• heterogeneous, homogeneous

Name the alkaline earth metal in period 4