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Sophie [7]
2 years ago
13

Potassium has a mass number of 40 and an atomic number of 19. how many protons does it have?

Chemistry
1 answer:
ratelena [41]2 years ago
6 0
19. The atomic number is the same as protons and electrons unless it have a - or a + charge the electrons are going to change
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What is neutralization ?
blagie [28]

Answer:

"a chemical reaction in which acid and a base react quantitatively with each other"

Explanation:

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2 years ago
For a titration of 25 ml of naoh solution, 23.30 ml of hcl solution if used. what is the molarity of naoh
Eduardwww [97]

<span>HCl<span>(aq)</span>+NaOH<span>(aq)</span>→NaCl<span>(aq)</span>+<span>H2</span>O<span>(l)</span></span>

As you can see here, one mole of acid neutralizes one mole of base.

We use the concentration equation, which states that,

<span>c=<span>nv</span></span>

<span> <span> <span> n is the number of moles </span> <span> v is the volume of solution </span> </span> </span>

Rearranging for moles, we get,

<span>n=c⋅v</span>

So, we have:

<span><span>n<span>NaOH</span></span>=0.1 M⋅0.05 L</span>

<span>=0.005 mol</span>

Since one mole of acid neutralizes one mole of base, then we must have: <span><span>n<span>HCl</span></span>=<span>n<span>NaOH</span></span></span>.

And so,

<span><span>c<span>HCl</span></span>=<span><span>n<span>HCl</span></span><span>v<span>HCl</span></span></span></span>

<span>=<span><span>0.005 mol</span><span>0.03 L</span></span></span>

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3 0
3 years ago
After he finished his work, Mendeleev predicted _____.
Alex17521 [72]

Answer:

the properties of three undiscovered elements  is the correct answer.

Explanation:

After he completed his work Mendeleev predicted the properties of the undiscovered elements.

In the year 1871, Dmitri Mendeleev predicted the detailed existence and the properties of the three elements that are undiscovered and he gained tremendous fame.

He left the gap in the table to put the elements which are not identified at that time and by glancing at the physical and chemical properties of an element next to the gap, Mendeleev could predict the properties of the not discovered elements.

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3 years ago
What information does the chemical shift of an nmr signal convey? select the correct answer?
alexdok [17]
The answer to your question is position and number of chemical shifts give information about the structure of a organic molecule. Chemical shift describes the relative positions of the resonances in an NMR spectrum. It is also the position on the δ scale (ppm - parts per million) where the peak occurs.
8 0
3 years ago
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A 17.9 mL sample of a 0.445 M aqueous hypochlorous acid solution is titrated with a 0.374 M aqueous sodium hydroxide solution. W
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the pH at the start of the titration is 3

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