All categories

4 years ago

Is calcium fluoride a pure substance, element, compound, or mixture?

Chemistry

2 answers:

Yuliya22 [10]4 years ago

7 0

compound

calcium and flourine

kenny6666 [7]4 years ago

3 0

Answer: The correct answer is compound.

Explanation:

A pure substance is defined as the substance which is formed by same or different type of atoms which are chemically combined in a fixed ratio by mass.

A compound is a substance which is formed by two or more different type of atoms when they chemically combine.

An element is defined as the substance which have only one type of atoms.

Mixture is defined as the solution which is made by the combination of two or more substances in which each substances retain their original chemical properties.

Calcium fluoride is made by the chemical combination of calcium and fluorine atoms. Thus, it is considered as a compound.

Hence, the correct answer is compound.

You might be interested in

Will the different flavors of khool aid effect the temperature of the boiling point

Andre45 [30]

No it does not effect the temperature of boiling point

8 0

3 years ago

Many double-displacement reactions are enzyme-catalyzed via the "ping pong" mechanism, so called because the reactants appear to

zhenek [66]

Answer:

D. It will decrease by a factor of 4

Explanation:

According to the question , the equation follows :

$A+B\rightarrow C+D$

Rate law : This states the rate of reaction is directly proportional to concentration of reactants with each reactant raised to some power which may or may not be equal to the stoichiometeric coefficient.

$Rate\ \alpha [A]^{a}[B]^{b}$

$r=[A]^{a}[B]^{b}$ .................(1)

STEP": First, find out the power "a" and "b"

a+b = 3 (because it is given that the reaction follow 3rd order-kinetics)

According to question, doubling the concentration of the first reactant causes the rate to increase by a factor of 2 means,

r' = 2r if [A'] = 2[A]

Here [B] is uneffected means [B']=[B]

hence new rate =

$r'=[A']^{a}[B']^{b}$

Put the value of [A'] , [B'] and r' in the above equation:

$2r=[2A]^{a}[B]^{b}$ ...........(2)

Divide equation (1) by (2) we , get

$\frac{2r}{r}=\frac{[2A]^{2}[B]^{b}}{[A]^{a}[B]^{b}}$

$2= 2(\frac{A}{A})^{a}\times (\frac{B}{B})^{b}$

Here A and A cancel each other

B and B cancel each other

We get,

$2= 2^{a}\times 1^{b}$

1^b = 1 ( power of 1 = 1)

$2= 2^{a}$

This is possible only when a = 1

We know that : a + b = 3

1 + b = 3

b =3 -1 = 2

b = 2

Hence the rate law becomes :

$r=[A]^{a}[B]^{b}$

$r=[A]^{1}[B]^{2}$ .............(3)

Look in the question now, it is asked to calculate the concentration of [B],if cut in half

Hence

[B']=1/2[B]

Insert the value of [B'] in equation (3)

$r'=[A]^{1}[B']^{2}$

$r'=[A]^{1}(\frac{1}{2}[B])^{2}$

$r'=\frac{1}{4}[A]^{1}[B]^{2}$ ............(a)

But

$r=[A]^{a}[B]^{b}$ ..............(b)

Compare equation (a) and (b) , we get

new rate r' =

r' = 1/4 r

7 0

3 years ago

A chunk of sulfur has a volume of 8.33 cm3. What is the mass of this sulfur? (Density of sulfur = 2.07 g/cm3.)

nata0808 [166]

Explanation:

equations to note:

density= mass/volume

mass= volume *density

volume= mass/density

you have a volume- 8.33cm3

you have a density- 2.07 g/cm3

Answer:

8.33cm3 * 2.07g/cm3= 17.24g

mass= 17.24g

5 0

3 years ago

Which pair of elements have the same valence electronic configuration of np³?

Dennis_Churaev [7]

Answer:

Explanation:

We can determine the number of valence electrons of an element:

If it belongs to Groups 1 and 2, the number of valence electrons is equal to the number of group and the differential electron occupies the s subshell.

If it belongs to the groups 13-18, the number of valence electrons is equal to: "Number of group - 10" and the differential electron occupies the p subshell.

Which pair of elements have the same valence electronic configuration of np³?

(a) O and Se. NO. They belong to the group 16 and the valence electron configuration is ns² np⁴.

(b) Ge and Pb. NO. They belong to the group 14 and the valence electron configuration is ns² np².

(d) K and Mg. NO. They belong to the groups 1 and 2 and the valence electron configuration is ns¹ and ns².

(e) Al and Ga. NO. They belong to the group 13 and the valence electron configuration is ns² np¹.

5 0

3 years ago

Is C3h8 an acid or base

Ronch [10]

That would be propane

Propane is neither an acid nor base, tis' neutral

7 0

4 years ago

Read 2 more answers