Endo Exo Chem Equations

A reaction occurs in a test tube you are holding---it starts to feel cold to you.

• endo

• exo

Tags

NGSS.HS-PS1-4

The prefix "exo" means

• "in"

• "out"

• "up"

• "down"

Energy must be ___ to break chemical bonds.

• added

• released

Energy must be ___ when new bonds are created.

• released

• absorbed

• created

• destroyed

2 As + 6 NaOH → 2 Na3AsO3 + 2 H2

Is the equation above a balanced chemical equation?

• No, because the reactants contain more hydrogen atoms than the products.

• Yes, because the mass of the reactants is equal to the mass of the products

• Yes, because the reactants contain the same number of Arsenic (As) atoms as the products.

• No, because the reactants contain more Oxygen atoms than the products.

In a chemical reaction, in order to make a product, you must either break apart or combine _________.

• enzymes

• reactants

• catalysts

• products

Which of the following chemical equations is balanced?

• Na + H₂O —> NaOH + H₂

• 2NaI + Pb(NO₃)₂ —> PbI₂ + NaNO₃

• MgCO₃ + 2HNO₃ —> Mg(NO₃)₂ + H₂O + CO₂

• HCl + Na₂S₂O₃ —> NaCl + SO₂ + S + H₂O

What is it called when one or more electrons are transferred from one atom to another?

• Covalent Bond

• Ionic bond

• Ion

• Anion

What is a cation?

• A negatively charged ion

• An atom with no charge

• A positively charged ion

• A stable atom on the periodic table

What is it called when two atoms share an electron?

• Ionic Bonding

• Covalent bonding

• Oxidation Number

• Valence Electron