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
vlada-n [284]
3 years ago
15

Use the definition of molarity to calculate the concentration of 12.34 g of CaSO4 completely dissolved in water, with a solution

volume of 250.0 mL as measured using a volumetric flask. The molar mass of CaSO4 is 136.13 g/mol. Answer with 4 significant digits and include an appropriate unit.
Chemistry
1 answer:
Ede4ka [16]3 years ago
8 0

Answer:

[CaSO₄] = 36.26×10⁻² mol/L

Explanation:

Molarity (M) → mol/L → moles of solute in 1L of solution

Let's convert the volume from mL to L

250 mL . 1L/1000 mL = 0.250L

We need to determine the moles of solute. (mass / molar mass)

12.34 g / 136.13 g/mol = 0.0906 mol

M → 0.0906 mol / 0.250L = 36.26×10⁻² mol/L

You might be interested in
S8 + 24 F2 ⟶ 8 SF6
Arturiano [62]

Answer:

Theoretical Yield of SF₆ = 2.01 moles

Explanation: If you understand and can apply the methodology below, you will find it applies to ALL chemical reaction stoichiometry problems based on the balanced standard equation; i.e., balanced to smallest whole number coefficients.

Solution 1:

Rule => Convert given mass values to moles, solve problem using coefficient ratios. Finish by converting moles to the objective dimensions.

Given      S₈            +          24F₂            =>    8SF₆

             425g                    229g                      ?

= 425g/256g/mol.      = 226g/38g/mol.

= 1.66 moles S₈          = 6.03 moles F₂ <= Limiting Reactant

<em>Determining Limiting Reactant => Divide moles each reactant by their respective coefficient; the smaller value will always be the limiting reactant. </em>

S₈ = 1.66/1 = 1.66

F₂ = 6.03/24 = 0.25 => F₂ is the limiting reactant

<em>Determining Theoretical Yield:</em>

Note: When working problem do not use the division ratio results for determining limiting reactant. Use the moles F₂ calculated from 229 grams F₂ => 6.03 moles F₂. The division procedure to define the smaller value and limiting reactant is just a quick way to find which reactant controls the extent of reaction.  

Given      S₈            +          24F₂            =>    8SF₆

             425g                    229g                      ?

   = 425g/256g/mol. = 226g/38g/mol.

= 1.66 moles S₈          = 6.03 moles F₂ <= Limiting Reactant

<em>Max #moles SF₆ produced from 6.03 moles F₂ and an excess S₈ </em>

Since coefficient values represent moles, the reaction ratio for the above reaction is 24 moles F₂ to 8 moles SF₆. Such implies that the moles of SF₆ (theoretical) calculated from 6.03 moles of F₂ must be a number less than the 6.03 moles F₂ given. This can be calculated by using a ratio of equation coefficients between 24F₂ and 8SF₆  to make the outcome smaller than 6.03. That is,

moles SF₆ = 8/24 x 6.03 moles = 2.01 moles SF₆ (=> theoretical yield)  

S₈ + 24F₂ => 8SF₆

moles SF₆ = 8/24(6.03) moles = 2.01 moles

You would NOT want to use 24/8(6.03) = 18.1 moles which is a value >> 6.03.        

This analysis works for all reaction stoichiometry problems.

Convert to moles => divide by coefficients for LR => solve by mole mole ratios from balanced reaction and moles of given.    

____________________

Here's another example just for grins ...

             C₂H₆O   +   3O₂     =>     2CO₂    + 3H₂O

Given:    253g          307g               ?               ?

a. Determine Limiting Reactant

b. Determine mass in grams of CO₂ & H₂O produced        

Limiting Reactant

moles  C₂H₆O = 253g/46g/mol = 5.5 moles  => 5.5/1 = 5.5

moles  O₂ = 307g/32g/mol = 9.6 moles         =><em>  9.6/24 = 0.4 ∴ O₂ is L.R.</em>

But the problem is worked using the mole values; NOT the number results used to ID the limiting reactant.  

 C₂H₆O   +       3O₂          =>     2CO₂    + 3H₂O

------------ 9.6 mole (L.R.)              ?               ?

mole yield CO₂ = 2/3(9.6)mole = 6.4 mole  (CO₂ coefficient < O₂ coefficient)

mole yield H₂O = 9.6mole  = 9.6mole (coefficients O₂ & CO₂ are same.)

mole used C₂H₆O = 1/3(9.6)mole = 3.2 mole (coefficient  C₂H₆O < coefficient O₂)

For grams => moles x formula weight (g/mole)

7 0
3 years ago
How many moles of C6Cl6 are in 5.44g
Kazeer [188]

Explanation:

rbrhrhyhggggsdffffffffffv

4 0
3 years ago
A solution has a pH of 12. Is it considered an
Mila [183]

Answer:

Base

Explanation:

5 0
3 years ago
Read 2 more answers
Identify the species oxidized. 2 al3+(aq) + 2 fe(s) → 2 al(s) + 3 fe2+(aq)
Sliva [168]
To know the answer, compare the oxidation number of the element in the reactant and the product side. The oxidation number of Al was originally +3, then became 0 after the reaction. On the other hand, Fe was originally 0, then became +2 after the reaction. When the element is oxidized, it oxidation number increases. <em>Thus, the element oxidized is Fe.</em>
8 0
3 years ago
Which of the following are true for an element?       (i)Atomic number= number of protons + number of electrons      (ii)Mass nu
fredd [130]

Answer:

<em>ii</em><em> </em><em>and</em><em> </em><em>iv</em><em> </em>

Explanation:

atomic mass is the sum of protons and neutrons

protons ( postively charged) usually have the same number like electrons( negatively charged)

4 0
2 years ago
Other questions:
  • What do you know about a chemical compound by looking at its chemical formula?
    13·2 answers
  • Help please?!??!??!?!?!
    13·1 answer
  • What is the density of an object with a mass of 1.663 g and a volume of 0.2009 mL
    14·2 answers
  • What is a cool 1 week or less science fair project for grade 9?
    13·2 answers
  • Define the following terms:
    5·1 answer
  • Does it take faster for sugar or color (tint) to dissolve in water and WHY?
    6·1 answer
  • What are the two parts of a solution?
    6·1 answer
  • Which of the following is a layer of the solid Earth?
    11·1 answer
  • Anyone wanna start a conversation
    8·2 answers
  • For the readion 2Na + Ch&gt; 2NaCl, how many grams of Ch are required to read completely with 450 g Na
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!