All categories

3 years ago

How would you prepare 2.5 L of a 0.800M solution of KNO3?

1 answer:

7 0

First find the mass of solute:

Molar mass KNO₃ = 101.1032 g/mol

mass = Molarity * molar mass * volume

mass = 0.800 * 101.1032 * 2.5

mass = 202.2064 g of KNO₃

To prepare 2.5 L (0800 M) of KNO3 solution, must weigh 202.2064 g of salt, dissolve in a Beker, transfer with the help of a funnel of transfer to a volumetric flask, complete with water up to the mark, capping the balloon and finally shake the solution to mix.

hope this helps!

You might be interested in

Why potasium more reactive than lithium and sodium

frez [133]

So potassium is more reactive than lithium because the outer electron of a potassium atom is further from its nucleus than the outer electron of a lithium atom. Hope this answers the question. Have a nice day. Feel free to ask more questions.

5 0

3 years ago

You are given a solution that is 518 mM lactose. You need to make up 4.5 L of 16.7 mM solution. What volume do you need to trans

OLga [1]

Answer:

The volume you need to transfer from the stock solution is 0.145 l

Explanation:

Since the number of moles of lactose in the volume of stock solution that you transfer will be the same as the number of moles of lactose in the final solution, you can use this expression:

number of moles in volume to transfer = number of moles in the final solution

Since number of moles = concentration * volume (if the concentration is expressed in molarity), then:

Ci * Vi = Cf * Vf

where:

Ci = concentration of the stock solution.

Vi = volume of the stock solution to be transferred.

Cf = concentration of the final solution

Vf = volume of the final solution

Then, replacing with the data:

518 mM * Vi = 16.7 mM * 4.5 l

Vi = 16.7 mM * 4.5 l / 518 mM

Vi = 0.145 l or 145 ml

Notice that any concentration unit can be used, as long as the units of the concentration of the stock and final solution are the same.

4 0

3 years ago

Help plssssssssssssssss??

ser-zykov [4K]

Answer:

Chemical properties, such as combustibility, are generally observed as the identity of a substance changes and one or more new substances form.

Explanation:

Chemical change involves formation of new substances. Therefore, the correct answer is "Chemical properties, such as combustibility, are generally observed as the identity of a substance changes and one or more new substances form."

8 0

2 years ago

IF YOU KNOW THE REST OF THE TEST'S ANSWERS PLEASE SHARE

Semenov [28]

Answer:

B. a state in which the forward and reverse reactions are proceeding at equal rates

Explanation:

"Chemical equilibrium is the state of a chemical system at which a constant concentration of products and reagents is present. Reactions, which take place in homogeneous solutions, seem to have come to rest because no changes in concentrations of the participating substances can be determined. Substance turnover occurs only on the particle level, which is why chemical equilibrium is also referred to as dynamic equilibrium."

3 0

2 years ago

Read 2 more answers

Use the molar heat capacity for aluminum from table 1 to calculate the amount of energy needed to raise the temperature of 260.5

Nimfa-mama [501]

Unfortunately, you failed to include the table 1 from which the molar heat capacity of aluminum could have been obtained. However, as a general rule, the heat needed to raise the temperature of a certain substance by certain degrees is calculated through the equation,
H = mcpdT
where H is heat, m is mass, cp is specific heat capacity, and dT is change in temperature. From a reliable source, cp for aluminum is equal to 0.215 cal/g°C. Substituting this to the equation,
H = (260.5 g)(0.215 cal/g°C)(125°C - 0)
H = 7000.94 cal

6 0

2 years ago