Introduction to Chemistry

Which elements conduct heat or electricity?

• Metals

• Non-Metals

• Noble Gases

• Metalloids

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NGSS.MS-PS3-3

Which element has an atomic number of 20?

• Sodium

• Magnesium

• Potassium

• Calcium

Which elements are stable and always on the move?

• Metals

• Non-Metals

• Noble Gases

• Metalloids

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NGSS.MS-PS3-1

When investigating a chemical reaction, one would expect the products to have

 

• The same properties as the reactants have separately

• a mixture of the properties of the reactants

• different properties than the reactants have separately

• the same properties as only one of the reactants

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which action represents a chemical change?

• melting gold

• running an electrical current through copper wire

• iron rusting in the course of time

• breaking an ice cube into smaller pieces

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NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following is the best evidence for a chemical change.

• bubbles are given off

• a precipitate is formed

• the formation of a new substance

• all the choices

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NGSS.MS-PS1-2

Why does increasing the concentration of reactants increase the reaction rate?

 

• Increasing the concentration of the reactants causes the reacting particles to have more energy.

• Increasing the concentration of the reactants causes the temperature to increase

• Packing more particles into a fixed volume increases the frequency of collisions

• Packing more particles into a fixed volume decreases the energy of the particles

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NGSS.HS-PS1-5

Which of the following pH values indicates the highest concentration of hydronium ions in a solution?

• pH = 1

• pH = 2

• pH = 12

• pH = 7

The reaction Cl₂(g) + 2KBr(aq) -> 2KCl(aq) + Br₂(l) is a(n)

• synthesis reaction

• decomposition reaction

• single-replacement reaction

• double-replacement reaction

The reaction Pb(NO₃)₂(aq) + 2KI(aq) -> PbI₂(s) + 2KNO₃(aq) is a

• synthesis reaction

• combustion reaction

• single-replacement reaction

• double-replacement reaction

Tags

NGSS.MS-PS1-2