Question

collection 2: create the multiple molecules indicated below
chemical formula\tname of molecule\t# of elements\t# of atoms\tsketch
\t\t\t\tball & stick model
\t2 carbon dioxide\t\t\t

\tmolecules\t\t\t
\t\t1 chlorine molecule\t\t\t
\t\t2 water molecules\t\t\t
\t\t2 ammonia\t\t\t

Explanation:

For 2 carbon dioxide ($\boldsymbol{2CO_2}$):

Step1: Determine Chemical Formula

The formula for carbon dioxide is $CO_2$, so 2 molecules is $2CO_2$.

Step2: Count # of Elements

In $CO_2$, elements are C (carbon) and O (oxygen), so 2 elements.

Step3: Count # of Atoms per Molecule

1 $CO_2$ has 1 C + 2 O = 3 atoms. For 2 molecules: $2\times(1 + 2)=6$ atoms.

For 1 chlorine molecule ($\boldsymbol{Cl_2}$):

Step1: Determine Chemical Formula

Chlorine molecule is $Cl_2$.

Step2: Count # of Elements

Only Cl (chlorine), so 1 element.

Step3: Count # of Atoms

1 $Cl_2$ has 2 atoms.

For 2 water molecules ($\boldsymbol{2H_2O}$):

Step1: Determine Chemical Formula

Water is $H_2O$, so 2 molecules is $2H_2O$.

Step2: Count # of Elements

Elements are H (hydrogen) and O (oxygen), so 2 elements.

Step3: Count # of Atoms per Molecule

1 $H_2O$ has 2 H + 1 O = 3 atoms. For 2 molecules: $2\times(2 + 1)=6$ atoms.

For 2 Ammonia ($\boldsymbol{2NH_3}$):

Answer:

Step1: Determine Chemical Formula

Ammonia is $NH_3$, so 2 molecules is $2NH_3$.

Step2: Count # of Elements

Elements are N (nitrogen) and H (hydrogen), so 2 elements.

Step3: Count # of Atoms per Molecule

1 $NH_3$ has 1 N + 3 H = 4 atoms. For 2 molecules: $2\times(1 + 3)=8$ atoms.

Filled Table:

Chemical Formula	Name of Molecule	# of elements	# of atoms	Sketch (Ball & Stick model)
$Cl_2$	1 chlorine molecule	1	2	(Sketch 1 $Cl_2$ model)
$2H_2O$	2 water molecules	2	6	(Sketch 2 $H_2O$ models)
$2NH_3$	2 Ammonia	2	8	(Sketch 2 $NH_3$ models)

(Note: The "Sketch" column would involve drawing ball - and - stick models: for $CO_2$, linear with C in the middle and O on either side; for $Cl_2$, two Cl atoms bonded; for $H_2O$, bent with O in the middle and H atoms; for $NH_3$, trigonal pyramidal with N in the middle and H atoms.)