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3 years ago

What is the mass number, symbol, and charge of an atom that contains 19 protons, 20 neutrons and 19 electrons?

Chemistry

1 answer:

Crazy boy [7]3 years ago

8 0

Answer:

Explanation:

mass number = 19 + 20 = 39 (protons + neutrons)

The charge is 0. This is an atom

The symbol = K

Protons: 19

Electrons: 19

Neutrons: 20

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What is the study of his matter and energy interact? A. Chemistry B. Physics C. Biology D. Planetary science

e-lub [12.9K]

The answer is option (B) Physics

8 0

3 years ago

Read 2 more answers

Complete the chart. (Remember to enter a 0 if necessary.)

Trava [24]

<span>Atomic Number 10 is Neon.

1s: 2
2s: 2
2p: 6
3s: 0
3p: 0
4s: 0
3d: 0
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2 years ago

Under standard-state conditions, which of the following half-reactions occurs at the cathode during the electrolysis of aqueous

Slav-nsk [51]

Answer:

The following reaction will occur at cathode:

$Ni^{+2}(aq)+2e--->Ni(s)$

Explanation:

The two half reaction during electrolysis of aqueous nickel sulfate will be

a) anode reaction :

Water will undergo oxidation and will evolve oxygen gas at anode as shown in the given reaction:

$2H_{2}O(l) ----> O_{2}(g) + 4H^{+}(aq) + 4e$

b) Cathode reaction: The reduction of Nickel ion will occur by gain of two electrons as shown in the given equation:

$Ni^{+2}(aq)+2e--->Ni(s)$

Thus the overall reaction will be:

$2H_{2}O(l) + 2Ni^{+2}----> O_{2}(g) + 4H^{+}(aq) + 2Ni(s)$

6 0

2 years ago

What does atomic mass on the periodic table represent?

neonofarm [45]

The atomic mass on the periodic table represents the sum of number of protons and number of neutrons.

Atomic mass = Number of protons + number of neutrons

Hope this helps!

6 0

3 years ago

What will happen to the pH of a buffer if acid/base ratio is increased by 100?

sp2606 [1]

Answer:

It will decrease by 2 units.

Explanation:

The Henderson-Hasselbalch equation for a buffer is

pH = pKa + log(base/acid)

Let's assume your acid has pKa = 5.

(a) If the base: acid ratio is 1:1,

pH(1) = 5 + log(1/1) = 5 + log(1) = 5 + 0 = 5

(b) If the base: acid ratio is 1:100,

pH(2) = 5 + log(1/100) = 5 + log(0.01) = 5 - 2 = 3

(c) Difference

ΔpH = pH(2) - pH(1) = 5 - 3 = -2

If you increase the acid:base ratio to 100:1, the pH will decrease by two units.

4 0

3 years ago