1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
nasty-shy [4]
3 years ago
6

How many formula units make up 12.8 g of magnesium chloride ( MgCl2)? Express the number of formula units numerically.

Chemistry
1 answer:
Advocard [28]3 years ago
8 0

Answer:

For 12.8 g there 0.807 × 10³ formula units.

Explanation:

Given data:

Mass of MgCl₂ = 12.8 g

Formula units for given mass = ?

Solution:

First of all we will calculate the number of moles.

Number of moles = mass/molar masss

Number of moles = 12.8 g/ 95.211 g/mol

Number of moles = 0.134 mol

According to the Avogadro number,

one moles = 6.022 × 10³ formula units

For 0.134 mol,

0.134 × 6.022 × 10³ formula units

0.807 × 10³ formula units

For 12.8 g there 0.807 × 10³ formula units.

You might be interested in
The pH of a 0.150 molar solution of a weak acid is 4.10. What is the pKa of the acid?
Kamila [148]
Answer: 4.21×10⁻⁸

Explanation:


1) Assume a general equation for the ionization of the weak acid:

Let HA be the weak acid, then the ionization equation is:

HA ⇄ H⁺ + A⁻

2) Then, the expression for the ionization constant is:

Ka = [H⁺][A⁻] / [HA]

There, [H⁺] = [A⁻], and [HA] = 0.150 M (data given)


3) So, you need to determine [H⁺] which you do from the pH.

By definition, pH = - log [H⁺]

And from the data given pH = 4.1


⇒ 4.10 = - log [H⁺] ⇒ [H⁺] = antilog (- 4.10) = 7.94×10⁻⁵

4) Now you have all the values to calculate the expression for Ka:

ka = 7.94×10⁻⁵ × 7.94×10⁻⁵ / 0.150 = 4.21×10⁻⁸
3 0
3 years ago
Read 2 more answers
A metal(ii) ion solution of unknown concentration shows an absorbance of 0.55. what is the molar concentration of the metal (ii)
torisob [31]
Cover with metal .Any elements other than hydrozen and helium concentration shows an absorbance
4 0
2 years ago
What happens to the sugars that are made during photosynthesis?
KiRa [710]
The sugars (c6h12o6) or the glucose that is made during photosynthesis is turned into glucose cellulose or starch that the plant can use for energy and food for the plant. Hope this helps.
8 0
3 years ago
What are 5 most abundant elements in the Earth's crust​
allochka39001 [22]

Explanation:

Element Abundance percent by weight Abundance parts per million by weight

Oxygen 46.1% 461,000

Silicon 28.2% 282,000

Aluminum 8.23% 82,300

Iron 5.63% 56,300

4 0
2 years ago
Read 2 more answers
If a chemical change has taken place, which of these is most likely true?
____ [38]
<span>C. A completely new substance is formed.</span>
5 0
2 years ago
Read 2 more answers
Other questions:
  • What is a supersaturated solution?
    11·1 answer
  • Rank the 4 phases of matter in order from slowest to fastest atom speed. And why
    8·2 answers
  • What new characteristic did John Delton add to the model of the atom BRAINLY WHOEVER GETS IT RIGHT PLEASE IM ON A TIMER
    13·1 answer
  • In the Lewis structure of BF3, how many lone pairs surround the boron atom?
    6·2 answers
  • During a hurricane, what effect can the ocean have on the beach?
    12·1 answer
  • How many moles in 4.93 x 10E23 atoms of silver?
    14·1 answer
  • Please help
    14·1 answer
  • Zn + O2= ZnO<br><br> How many moles of zinc are needed to make 500. g of zinc oxide?​
    6·1 answer
  • How are elements in the same family in the periodic table alike?
    5·2 answers
  • Write the general electron configuration of a transition element(b) in Period 6.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!