Question

1. use what you have just learned about chemical formulas to identify each of the following as an element, a compound or a mixture.

a. br₂
b. nahco₃
c. c₆h₁₂o₆ & h₂o
d. cu & zn
e. co₂
f. al

Explanation:

Step1: Recall definitions

An element is a pure - substance made of only one type of atom. A compound is a pure - substance made of two or more different types of atoms chemically combined. A mixture is a combination of two or more substances that are not chemically combined.

Step2: Analyze a. $Br_2$

$Br_2$ is a diatomic molecule of bromine. It is made of only bromine atoms, so it is an element.

Step3: Analyze b. $NaHCO_3$

$NaHCO_3$ (sodium bicarbonate) is made of sodium (Na), hydrogen (H), carbon (C), and oxygen (O) atoms chemically combined, so it is a compound.

Step4: Analyze c. $C_6H_{12}O_6\&H_2O$

This is a combination of glucose ($C_6H_{12}O_6$) and water ($H_2O$) which are not chemically combined, so it is a mixture.

Step5: Analyze d. $Cu\&Zn$

This is a combination of copper (Cu) and zinc (Zn) which are not chemically combined, so it is a mixture.

Step6: Analyze e. $CO_2$

$CO_2$ (carbon - dioxide) is made of carbon (C) and oxygen (O) atoms chemically combined, so it is a compound.

Step7: Analyze f. $Al$

$Al$ (aluminum) is made of only aluminum atoms, so it is an element.

Answer:

a. Element
b. Compound
c. Mixture
d. Mixture
e. Compound
f. Element