Achemist needs 90 milliliters of a 72% solution but has only 68% and 77% solutions available. find how many milliliters of the 68% solution should be mixed with the 77% solution to get the desired strength.

Mix 50 mL of the 68% solution with 40 mL of the 77% solution to make 90 mL of the 72% solution.

Explanation:

Let the volume required of the 68% solution be mL. The volume of the 68% solution and the 77% solution shall add up to 90 mL. Thus the volume required of the 77% solution shall be mL.

The amount of solute in the 72% solution will be:

.

The mL of the 68% solution will contribute:

.

The mL of the 77% solution will contribute:

.

The two values shall add up to . That is:

.

.

.

In other words, there need to be

it is to be noted that an alpha particle is an helium nucleus. so it contains 2 protons 2 neutrons and has a mass number of 4. when alpha decay particles are ejected from the nucleus it gets transformed into an atom which has atomic number less than 2 and a mass number less than 4.

an equation that could represent alpha decay is radium 226 decay of alpha particle forms radon 222.

→

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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