7H UNIT 2

Marsha is investigating the following chemical reaction: 2Al + 3CuCl₂ → 3Cu + 2AlCl₃. She wants to use the equation to predict the mass of the products that will form. What does this equation indicate about the atoms before and after the reaction?

• The mass of the products will be the same as the mass of the reactants because there will be 2 atoms of Al, 3 atoms of Cu, and 6 atoms of Cl before and after the reaction.

• The mass of the products will be the same as the mass of the reactants because there will be 2 atoms of Al, 6 atoms of Cu, and 6 atoms of Cl before and after the reaction.

• The mass of the products will be greater than the mass of the reactants because 2 atoms of Cl will change into 3 atoms of Cl in the products.

• The mass of the products will be greater than the mass of the reactants because 2 atoms of Al in the reactants will change into 6 atoms of Al in the products.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

4Na + 2O₂ → 2Na₂O How many sodium atoms are produced in one sodium oxide molecule?

• one

• two

• three

• four

Tags

NGSS.MS-PS1-1

Use the words to complete the information about chemical reactions, check options by correct order?

________represent the rearrangement of atoms of reactants to form new substances as products when they undergo a ________ . Each element is represented by a unique _________ that can be found on the​ ___________ , and each molecule is represented by _________

• chemical symbol, chemical equations, chemical formula, Periodic Table, chemical reaction

• chemical reaction, chemical equations, chemical formula, Periodic Table, chemical symbol

• chemical reaction, chemical symbol, chemical formula, Periodic Table, chemical reaction

• chemical equations, chemical reaction, chemical formula, Periodic Table, chemical symbol

Tags

NGSS.MS-PS1-1

Taleah conducts a chemical reaction and wants to know the number of hydrogen atoms in the products. Hydrogen only appears in the compound 2H₂O in the reactants. How many hydrogen atoms must be in the products?

• There must be 8 hydrogen atoms in the products, because mass increases from reactants to products.

• There must be 4 hydrogen atoms in the products, because the total mass is conserved.

• There must be 2 hydrogen atoms in the products, because the total mass is conserved.

• There must be 6 hydrogen atoms in the products, because mass decreases from reactants to products.

Tags

NGSS.MS-PS1-5

Use the words to complete the information about chemical reactions. [_____] represent the rearrangement of atoms of reactants to form new substances as products when they undergo a [_____]. Each element is represented by a unique [_____].

• chemical equations, chemical reaction, chemical symbol

• chemical symbols, chemical equation, chemical reaction

• chemical reactions, chemical symbol, chemical equation

• chemical elements, chemical reaction, chemical equation

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

__________ that can be found on the __________, and each molecule is represented by a __________.

• elements, periodic table, chemical formula

• compounds, solar system, atomic number

• atoms, food chain, electron shell

• minerals, weather map, isotope symbol

Tags

NGSS.MS-PS1-1

Enter the number of oxygen atoms in each of the following compounds. Glucose: C₆H₁₂O₆

• 4

• 5

• 6

• 8

Tags

NGSS.MS-PS1-1

Enter the number of oxygen atoms in each of the following compounds. Calcium Nitrate: Ca(NO₃)₂ ________

• 6

• 2

• 3

• 4

Tags

NGSS.MS-PS1-1

Enter the number of oxygen atoms in each of the following compounds. Carbon Monoxide: CO ________

• 1

• 2

• 0

• 3

Tags

NGSS.MS-PS1-1

Indicate the number of MOLECULES are in each of the following situations. 6CO ________

• 6

• 12

• 3

• 1