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3 years ago

Why do we need to standardize EDTA in determination of water hardness?

1 answer:

3 0

Standardized means that a specific amount EDTA is added to a specific volume of distilled water. Water hardness is determined by the the amount of a standard EDTA solution to change the color of the water from red to blue. For example if one added the correct amount of EDTA to twice the volume of distilled water the solution would be weak. Titration of the hard water would give a erroneous high result.

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How do i salve 50,200 mL to L

sveta [45]

You will have divided 50200 by 1000000 which 0.0502

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3 years ago

My science teacher trying to be cool

Helga [31]

Answer:

omg lol XD

Explanation:

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2 years ago

A gas at 325 k has a volume of 4.0 L. If the gas’s volume changes to 2.0 L at constant pressure, what will be the new temperatur

inessss [21]

4/325 = 2/unknown temperature
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4 years ago

Read 2 more answers

A gas occupies a volume of 650.0 mL when the pressure is 3.50 atm. What will the new volume be if the pressure is reduced to 1.6

Gemiola [76]

The new volume will be 1379 mL.

Explanation:

As per Boyle's law, the product of initial volume and initial pressure of any gas molecule is equal to the product of final volume and final pressure of those molecules.

So here the initial volume is 650 ml and the initial pressure is 3.50 atm. As the temperature is said to be constant, then this system will be obeying Boyle's law. So, the final pressure is given as 1.65 atm. As there is a reduction in the pressure, the volume of the gas is tend to get expanded.

$P_{1} V_{1} = P_{2} V_{2}$

So, $(650*10^{-3}*3.50)=(1.65*V_{2})$

$V_{2} = \frac{650*10^{-3}*3.50}{1.65} = 1379 mL$

So, the new volume of the gas on reduction in pressure is 1379 mL.

7 0

3 years ago

When radium-226 (atomic number-88) decays by emitting an alpha particle it becomes _____.

topjm [15]

Answer:

d. Radon-222

Explanation:

²²⁶₈₈Ra → ²²²₈₆Rn + ⁴₂He

Alpha particle is a helium nucleus with mass number 4 and atomic number 2. According to the law of conversation of mass, the sum of the mass number and atomic number must be equal on both side of the reaction.

Since the mass number of Ra is 226 and that of He is 4. The mass number of the unknown element must be 226 - 4 = 222.

Since the atomic number of Ra is 88 and that of He is 2. The atomic number of the unknown element must be 88 - 2 = 86.

Now looking in the periodic table Radon is the only element with atomic number 86.

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3 years ago

Why do we need to standardize EDTA in determination of water hardness?​

Why do we need to standardize EDTA in determination of water hardness?