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3 years ago

Determine the average atomic mass of the following mixture of isotopes of Potassium:

Chemistry

1 answer:

dexar [7]3 years ago

5 0

Answer

the first one (im pretty sure)

Explanation:

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Recessive genes are _____.

AveGali [126]

Answer:

1) represented by a lower case letter
2) always masked by dominant genes

3) only expressed in the absence of a dominant gene

Explanation:

So if I take a black and a yellow marker- and tried drawing the yellow over the black- or the other way around- you'd still only see the black marker. The recessive trait is like the yellow marker. Now if I drew the yellow marker with another yellow marker you would see the yellow. I hope this helps!

8 0

2 years ago

Why should you prefer dry ashing to wet ashing of food sample such as cabbage

julia-pushkina [17]

Answer:

Wet ashing is primarily used in the preparation of samples for subsequent analysis of specific minerals . It breaks down and removes the organic matrix surrounding the minerals so that they are left in an aqueous solution

Explanation:

8 0

2 years ago

Select all the correct answers.

pantera1 [17]

Answer:

B: Fission reactors generate huge amounts of heat.

C: Fission breaks down unstable elements such as uranium in a breeder reactor which is broken down in the process of fusion which is literally breaking down of elements.

E: fission is used in nuclear weapons as it is easier to accomplish then fusion bombs

Explanation:

A: as a zero-waste energy source

B: for generating large amounts of heat

C: for creating stable elements from unstable ones

D: for creating new, heavier elements

E: as the energy source in nuclear weapons

4 0

3 years ago

In this experiment we will be using a 0.05 M solution of HCl to determine the concentration of hydroxide (OH-) in a saturated so

gulaghasi [49]

<u>Answer:</u> The moles of hydroxide ions present in the sample is 0.0008 moles

<u>Explanation:</u>

To calculate the concentration of acid, we use the equation given by neutralization reaction:

$n_1M_1V_1=n_2M_2V_2$

where,

$n_1,M_1\text{ and }V_1$ are the n-factor, molarity and volume of acid which is HCl.

$n_2,M_2\text{ and }V_2$ are the n-factor, molarity and volume of base which is $Ca(OH)_2$

We are given:

$n_1=1\\M_1=0.05M\\V_1=16mL\\n_2=2\\M_2=?M\\V_2=36.0mL$

Putting values in above equation, we get:

$1\times 0.05\times 16=2\times M_2\times 36\\\\M_2=\frac{1\times 0.05\times 16}{2\times 36}=0.011M$

To calculate the moles of hydroxide ions, we use the equation used to calculate the molarity of solution:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution (in mL)}}$

Molarity of solution = 0.011 M

Volume of solution = 36.0 mL

Putting values in above equation, we get:

$0.011=\frac{\text{Moles of }Ca(OH)_2\times 1000}{36}\\\\\text{Moles of }Ca(OH)_2=\frac{0.011\times 36}{1000}=0.0004mol$

1 mole of calcium hydroxide produces 1 mole of calcium ions and 2 moles of hydroxide ions.

Moles of hydroxide ions = (0.0004 × 2) = 0.0008 moles

Hence, the moles of hydroxide ions present in the sample is 0.0008 moles

8 0

3 years ago

Is a candle melting in the hot sun a chemical or a physical change?

alukav5142 [94]

Chemical, because it is breaking down the chemical and properties in the candle itself.

4 0

3 years ago