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
Fed [463]
3 years ago
5

Please help me please

Chemistry
1 answer:
Roman55 [17]3 years ago
3 0

Answer:

Explanation:

Molarity = moles / volume (L)

moles = mass (g) / Molecular weight (g/mol)

so you have mass in gram and volume in ml ( Volume must be in litter because unit of mass is gram )

g = L     ,   mg = ml

first you must calculate the number of moles for each molecule and convert the ml to L and use the molarity law to calculate molarity for each molecule .

Ex71.

a.   Mw for NaCl = 23+35 = 58 g/mole

no of moles = 1.5 / 58 = 0.025

ml to L = 100/1000 = 0.1 L

Molarity = 0.025 / 0.1 = 0.25 M

b. Mw for K2CrO4 = 39x2 + 52 + 16x4 = 194 g/mol

no of moles = 1.5 / 194 = 0.0077

ml to L = 100 / 1000 = 0.1 L

Molarity = 0.0077 / 0.1 = 0.077 M

----------------------------------------------

Ex 72

a.  Mw for MgBr = 24 + 80 = 104 g/mol

no of moles = 20 / 104 = 0.19

ml to L = 250 / 1000 = 0.25 L

Molarity = 0.19 / 0.25 = 0.76 M

b. Mw for LiCO = 7 + 12 + 16 = 35 g/mol

no of moles = 5.55 / 35 = 0.158 moles

ml to L = 75 / 1000 = 0.075 L

Molarity = 0.158 / 0.075 = 2.106 M

Good Luck

You might be interested in
2 H2O2(aq) ----> 2 H2O(l) + O2(g) in the presence of I-(aq) is proposed to be: Step 1 (slow): H2O2 + I- -----> H2O + OI- S
andrezito [222]

Answer:

Molecularity of the rate determining step = 2

Explanation:

Step 1 (slow): H₂O₂ + I⁻ -----> H₂O + OI⁻

Step 2 (fast): H₂O₂ + OI⁻ -----> H₂O + O₂ + I⁻

The rate determining step in a reaction mechanism is also considered as slowest step.

Slowest step is also considered its highest activation energy in energy profile diagram.

In this case intermediate  (IO⁻) is formed.

Step 1 considered as a slowest step.

So,  Rate = K [H₂O₂][I⁻]

  Molecularity = 2

6 0
3 years ago
the Temperature of a sample of an ideal gas in a sealed 5.0 l container is raised from 27 oC to 77oC. If the initial pressure of
matrenka [14]
Answer:
              The pressure increases to 3.5 atm.

Solution:
                According to Gay-Lussac's Law, " At constant volume and mass the pressure of gas is directly proportional to the applied temperature".

For initial and final states of a gas the equation is,

                                           P₁ / T₁  =  P₂ / T₂
Solving for P₂,
                                           P₂  =  P₁ T₂ / T₁    ----- (1)

Data Given;
                   P₁  =  3 atm

                   T₁  =  27 °C + 273  =  300 K
 
                   T₂  =  77 °C + 273  =  350 K

Putting values in eq. 1,

                                           P₂  =  (3 atm × 350 K) ÷ 300 K

                                           P₂  =  3.5 atm
7 0
3 years ago
What is the scientific name for the substance that is dissolving in a solution?
Goryan [66]

Answer:

The solute is the substance that is being dissolved,

Explanation:

A solution is a homogeneous mixture consisting of a solute dissolved into a solvent .

4 0
2 years ago
Read 2 more answers
Which type of bond is present within a water molecule
krok68 [10]

Answer:

Covalent bonds

Explanation:

3 0
3 years ago
A crystal is a solid (or liquid) in which the constituent atoms, molecules, or ions are packed to have a ________________ as wel
yan [13]

Answer:

long range order

Explanation:

A crystal consists of atoms, ions or molecules having both short range and long range order. The atoms, ions or molecules are arranged in a regular pattern throughout the lattice both at immediate vicinities and across the entire crystal structure.

This order accounts for the definite shape and unique properties of crystals which include their sharp melting and boiling points which distinguishes them from amorphous substances.

6 0
3 years ago
Read 2 more answers
Other questions:
  • Why is maple syrup more diluted than maple sap
    14·1 answer
  • How many moles are in 28 grams of co2
    9·2 answers
  • How many moles of aluminum hydroxide would be produced from 4.6 miles of calcium hydroxide
    15·1 answer
  • A distance force is a force that acts on an object but
    5·2 answers
  • As you climb through the troposphere, the temperature:
    10·1 answer
  • what is the amount of charge that passes through a wire in a given period if time is the rate of electric
    12·2 answers
  • Strontium, a group 2 element with an electron configuration of 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 , will form a _____
    9·1 answer
  • Which is the symbol for the element that contains six electrons in each of its neutral atoms?
    5·1 answer
  • A cougar with a mass of 80 kg is standing at the edge of a cliff. Find the cougar’s potential energy if the cliff is 70 m high
    13·2 answers
  • Read the sentences from the Newsela article, "First All-Female Spacewalk Will Take Place During Women's History Month. "
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!