Chemistry, 28.09.2019 00:00 romeojose2005

Find the empirical formula of a compound which contains 54.93% potassium, 38.73% boron and 6.34% hydrogen.
a.
kbh
b.
kb2h4
c.
kb3h9
d.
k2b5h9

Answers: 1

Show answers

Answers

Answer from: mmcdaniels46867

Hello!

Find the empirical formula of a compound which contains 54.93% potassium, 38.73% boron and 6.34% hydrogen.

A. KBH

B. KB2H4

C. KB3H9

D. K2B5H9

We have the following data:

Potassium (K) ≈ 39 a.m.u (g/mol)

Boron (B) ≈ 11 a.m.u (g/mol)

Hydrogen (H) ≈ 1 a.m.u (g/mol)

We use the amount in grams (mass ratio) based on the composition of the elements, see: (in 100g solution)

K: 54.93 % = 54.93 g

B: 38.73 % = 38.73 g

H: 6.34 % = 6.34 g

The values (in g) will be converted into quantity of substance (number of mols), dividing by molecular weight (g / mol) each of the values, we will see:

$K: \dfrac{54.93\:\diagup\!\!\!\!\!g}{39\:\diagup\!\!\!\!\!g/mol} \approx 1.408\:mol$

$B: \dfrac{38.73\:\diagup\!\!\!\!\!g}{11\:\diagup\!\!\!\!\!g/mol} \approx 3.521\:mol$

$H: \dfrac{6.34\:\diagup\!\!\!\!\!g}{1\:\diagup\!\!\!\!\!g/mol} = 6.34\:mol$

We realize that the values found above are not integers, so we divide these values by the smallest of them, so that the proportion does not change, let us see:

$K: \dfrac{1.408}{1.408}\to\:\:\boxed{K = 1}$

$B: \dfrac{3.521}{1.408}\to\:\:\boxed{B \approx 2.5}$

$H: \dfrac{6.34}{1.408}\to\:\:\boxed{H \approx 4.5}$

convert number of atomic radio into whole number

2 * (1 : 2.5 : 4.5)

= 2 : 5 : 9 ← whole number of atomic radio

K = 2

B = 5

H = 9

Thus, the minimum or empirical formula found for the compound will be:

$\boxed{\boxed{K_2B_5H_9}}\Longleftarrow(Empirical\:Formula)\:\:\:\:\:\:\bf\green{\checkmark}$

D. K2B5H9

________________________

$\bf\blue{I\:Hope\:this\:helps,\:greetings ...\:Dexteright02!}\:\:\ddot{\smile}$

Answer from: Quest

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms

Answer from: Quest

the answer is minerals.

Another question on Chemistry

Chemistry, 22.06.2019 01:30

Pls! plant cells and animal cells were observed under a microscope. the characteristics of two cells are listed below. cell p: does not capture sunlight cell q: has cytoplasm but no chloroplast which statement about the two cells is correct? cell q also has a cell wall. cell q also has large vacuole. cell p also has a large vacuole. cell p also has a cell membrane.

Answers: 1

Answer

Chemistry, 22.06.2019 11:00

What is the temperature of 0.750 mol of a gas stored in a 6,850 ml cylinder at 2.21 atm? . 2.95 k 5.24 k 138 k 246 k

Answers: 3

Answer

Chemistry, 23.06.2019 04:00

Which method would be best to separate a mixture of sand and gravel

Answers: 1

Answer

Chemistry, 23.06.2019 06:00

What physical property of gold makes panning a useful way to get gold from streams?