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LOCOM Word Problems

LOCOM Word Problems

Assessment

Presentation

Science

7th Grade

Practice Problem

Easy

NGSS
MS-PS1-5, MS-PS1-2, MS-ESS1-1

+7

Standards-aligned

Created by

Tiffany Moore

Used 4+ times

FREE Resource

4 Slides • 15 Questions

1

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2

Multiple Choice

Question image

The partial periodic table and table contain information about silicon dioxide and sodium chloride. Which correctly uses evidence to describe one of the molecules?

1

Silicon dioxide is a covalent compound because of its conductivity and pliability.

2

Sodium chloride is not a covalent compound because of its conductivity and pliability.

3

Multiple Choice

Question image

The list of properties represents an element from one of the four highlighted positions.

1. It exists as a solid at room temperature.

  1. It is shiny and able to be bent.

  1. It has only 2 electrons in its outer orbital.

  2. It can easily react with oxygen and other nonmetals.

    In which position is this element located on the periodic table?

1

P

2

Q

3

R

4

S

4

Practice Word Problems

We are now going to be looking at practice word problems for today and tomorrow. You are going to be using either addition or subtraction. I do recommend having out some notebook paper (use your science notebook) and something to write with. You will also want to have your calculator on your laptop opened for this or bring out your own calculator. Let's start!

5

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6

Draw

For this problem you will need to write in a stand-in chemical equation and solve for the mass of reactant B.

7

Draw

Calculate the amount of substance C that must have formed in the reaction.

8

Draw

Calculate the total mass of MgO2 formed in the reaction.

9

Draw

Calculate how much oxygen was used in the reaction.

10

Draw

Calculate how much calcium chloride forms.

11

Draw

How much chlorine gas was used in the reaction?

12

Draw

Calculate how much sodium chloride was present before the reaction happened.

13

Draw

Calculate the mass of sodium formed in the reaction.

14

Multiple Choice

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In the reaction shown, how much manganese oxide (MnO) would be produced from the decomposition of potassium permanganate (KMnO4)?

1

30g

2

72g

3

102g

15

Multiple Choice

Question image

In the reaction shown, how much nitrogen (N2) would be necessary to produce 87g of ammonia (NH3)?

1

87g

2

53g

3

34g

16

Multiple Select

Question image

Which THREE equations could be represented by the model shown?

1

2LiCl   →   2Li   +   Cl2

2

2H2O  →   2H2   +   O2

3

2NaCl   →  2Na   +   Cl2

4

2LiBr  →  2Li   +   Br2

5

2HNO3  →  NO2   +   O2   +   H2O

17

Multiple Choice

Which of the following equations does not support the Law of Conservation of Mass? Show your work in your science notebook.

1

4NH3  +  5O2  →  4NO  +  6H2O

2

2As  +  4NaOH  →  2Na3AsO3  +  3H2

18

Multiple Choice

When a chemical reaction occurs, according to the Law of Conservation of Mass, matter cannot be created or destroyed.  If this is true, how do new products form?

1

Chemical bonds cannot be broken so the atoms do not rearrange to form new products.

2

 Chemical bonds are broken, the atoms rearrange, new bonds form between the atoms of the new products.

19

Do Now:

Haunted Mansion in Google Classroom

Now that we have work on a few word problems, go to Google Classroom, select today's date, and select the Genially Haunted Mansion that is linked.
Once done, you may work on any missing work for me in science or extras in Google Classroom.

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