Unit 04 Review

Hydrogen Peroxide has the chemical formula H₂O₂. Which statement correctly states the number of hydrogen and oxygen atoms present in the chemical formula?

• There is an equal number of hydrogen and oxygen atoms

• There is one Hydrogen atom for every two oxygen atoms

• there are two hydrogen atoms for every one oxygen atom

• there are two hydrogen atoms for every four oxygen atoms

Which of the following is a compound?

• H

• Fe

• Cl

• CO

Which substance in the following equation represents an element?

CH₄ + 2O₂ ----> CO_{2 +} 2H₂O

• CH₄

• 2O₂

• CO₂

• 2H₂O

Which of the following can only be found on the elements side of the venn diagram?

I.) Is a pure substance

II.) Made from more than one element

III.) Formed through a chemical reaction

IV.) Found on a periodic table

V.) Essential for life

VI.) Found on earth

• II, III

• I, IV

• All of the above

• I only

The products of the chemical equation can best be described as -

6CO₂ + 6H₂O ---> C₆H₁₂O₆ + 6O₂

• Two compounds

• Two elements

• One compound and one element

• One isotope and one molecule

What do Ca, C and O represent in the chemical formula CaCO₃?

• Elements

• Compounds

• Mixtures

• Molecules

A new compound has just been developed. Its formula is: NaPbKClArH. How many elements make up this compound?

• 5

• 6

• 10

• 7

During a science investigation, a places a small amount of butter in a pan. Which of the following would be the best evidence that a change in the chemical properties of the butter has taken place?

• The butter melts

• the butter gets hot

• the butter turns black

• the butter spreads out

What kind of properties can only be observed when a substance changes into a different substance?

• physical properties
• chemical properties
• liquid properties
• real properties

Tags

NGSS.MS-PS1-2

Which of the following is a sign that a chemical reaction has occurred?

• change in shape
• melting
• formation of a gas
• dissolving

Tags

NGSS.MS-PS1-2