Chemical Reactions Review

A chemist mixed two samples together: a brown solid that melts at about 1,300°C and a colorless liquid that melts at about 20°C. She analyzed the results and found two ending substances. One of the ending substances melts at about 250°C. This ending substance is made up of the repeating group of atoms shown above. Which of the diagrams to the left shows the repeating groups of atoms that make up the samples the chemist mixed together?

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Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Devorah is a food chemist, and she is developing a chemical to help foods stay fresh longer. She mixed a red liquid substance and a colorless solid substance together in a sealed container.

The diagram above shows the repeating groups of atoms that make up the two starting substances.

After mixing, Devorah found two white substances in the sealed container. (Nothing had escaped.)

Which of the diagrams to the left shows the repeating groups of atoms that make up the ending substances?

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Samira watched a demonstration in which a scientist combined two substances in a sealed container and analyzed the results. The ending substances did not look the same as the starting substances. Samira was given a diagram with the repeating groups of atoms that make up the starting substances, plus information about the properties of the starting and ending substances. She created a model of the repeating groups of atoms that might make up the two ending substances.

• Samira's model correctly demonstrates how the properties changed with the rearrangement of the atoms. However not all atoms are accounted for. There is a missing reactant.

• Samira's model is correct because the properties are different and the atoms are rearranged.

• Samira's model is incorrect because not all atoms are accounted for

• Samira's model correctly demonstrates how the properties changed with the rearrangement of the atoms. However not all atoms are accounted for. There is an extra product, that shouldn't be in her model.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Will the properties of the two samples likely be the same or different?

• The properties will likely be different because the repeating groups of atoms that make up each sample are different.

• The properties will likely be different because there are more repeating groups of atoms in Sample 2.

• The properties will likely be the same because the repeating groups of atoms that make up the two samples have the same number of atoms.

• The properties will likely be the same because the repeating groups of atoms that make up the two samples have two of the same types of atoms.

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

The substances at the beginning of a chemical equation are called the ____

• products

• yield

• chemical equation

• reactants

Tiahna mixed two solid substances together in a sealed container. After mixing, Tiana found two liquid substances in the sealed container. (Nothing had escaped.) Which of the repeating groups of atoms could make up the ending substances?

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Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Damian mixed two samples together shown above and found two products, only one is shown above. Which of the following could be the two samples he mixed together?

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Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Marisol mixed two samples together shown above and found two products, only one is shown above. Which of the following could be the two samples he mixed together?

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Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What are Chemical Reactions?

• It's when you mix substances.

• A process in which atoms rearrange to form new substances.

• When something bubbles.

• Letter and numbers showing the types and number of atoms.

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Serena mixed 2 samples. She analyzed the results and found two ending substances. One of the ending substances was a white solid. Which of the diagrams shows the repeating groups of atoms that make up the samples Serena mixed together?

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Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2