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Keiko needs 100mL of a 5% acid solution for a science experiment. She has available a 1% solution and a 6% solution. How many mi

4vir4ik [10]

Answer:

Keiko should mix 20 mL 1% solution and 80 mL 6% solution for to make 100 mL 5% solution

Explanation:

There are 2 unknown values X= mL 6% solution and Y=1% solution. So, we need 2 equations:

1. Equation acid concentration. X mL 6% + Y mL 1% = 100 mL 5%

2. Equation solvent concentration X mL 94% + Y mL 99% = 100 mL 95%

When clearing X and Y :

(X mL 6% + Y mL 1% = 100 mL 5%) (-15,7)

X mL 94% + Y mL 99% = 100 mL 95%

_______________________________

- Y 0.83 = 16.5

Y = 19.9 mL 1% solution

Replace Y in anyone equation and X = 80 mL 6% solution

I hope to see been helpful

7 0

3 years ago

Read 2 more answers

Na2o + h2so4 ———> na2so4 + h2o<br><br><br> Can anyone balance this please!!??

marysya [2.9K]

Answer:

The equation is already balanced. There's an equal number of materials on each side of the equation.

4 0

3 years ago

Activity

lina2011 [118]

Opinions are differ from facts as that we cannot change the facts but opinions can be changed as in first example it is given anthracite is better than bituminous coal may be there is another coal which is more better than anthracite. So here opinion is changed.

It is a black or brownish black sedimentary rock. It contains Sulphur, hydrogen, oxygen, carbon etc. It is always preferred as fuel. Coal was formed millions years ago when plant decay in the soil. It is obtained from dead vegetation. It is obtained from dead plants matter decay into peat and then it is converted into the coal by the process of heat.

<h3>What is Solar System ?</h3>

Solar System is made up of all the planets that revolve around our Sun. Solar System contains eight planets. These planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

Thus from the above conclusion we can say that Opinions are differ from facts as that we cannot change the facts but opinions can be changed as in first example it is given anthracite is better than bituminous coal may be there is another coal which is more better than anthracite. So here opinion is changed.

Learn more about the Coal here: brainly.com/question/16607139

#SPJ1

8 0

1 year ago

How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction? 4 KNO3(s) → 2 K2O(s) + 2

Leya [2.2K]

Answer:

0.725 mol

Explanation:

Moles are calculated as the given mass divided by the molecular mass.

i.e. ,

moles = ( mass / molecular mass )

since,

mass of KNO₃ = 58.6 g ( given )

Molecular mass of KNO₃ = 101 g / mol

Therefore,

moles of KNO₃ = 58.6 g / 101 g / mol

moles of KNO₃ = 0.58 mol

From the balanced reaction ,

4 KNO₃ (s) ---> 2K₂O (s) + 2N₂ (g) + 5O₂ (g)

By the decomposition of 4 mol of KNO₃ , 5 mol of O₂ are formed ,

hence, unitary method is used as,

1 mol of KNO₃ gives 5 / 4 mol O₂

Therefore,

0.58 mol of KNO₃ , gives , 5 / 4 * 0.58 mol of O₂

Solving,

0.58 mol of KNO₃ , gives , 0.725 mol of O₂

Therefore,

58.6g of KNO₃ gives 0.725 mol of O₂.

3 0

2 years ago

What is the name of the binary molecule H2O2? This compound is also known as hydrogen peroxide and is a properly disinfectant or

Masteriza [31]

Answer:

hydrogen dioxide

Explanation:

3 0

3 years ago