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3 years ago

Plz help thx brainliest btw :)

Chemistry

2 answers:

katrin2010 [14]3 years ago

8 0

I’m gonna answer so you can mark the person above brainliest.

Marina86 [1]3 years ago

3 0

Answer:

1. earth metal 2. halogen 3.The elements are arranged in seven horizontal rows, called periods or series, and 18 vertical columns, called groups. ... Elements in the periodic table are organized according to their properties.

Inventor: Dmitri Mendeleev please name most brainliest

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What is the Net Ionic Equation of the chemical equation (NH4)2S(aq) + 2KOH(aq) -> K2S(aq) + 2NH4OH(s)?

tangare [24]

Answer:

Chemical Equation: (NH4)2S(aq) + 2KOH(aq) -> K2S(aq) + 2NH4OH(s)

Explanation:

8 0

3 years ago

Which of the following has the largest number of molecules? a 1 g of benzene, C6H6 b 1 g of formaldehyde, CH2O c 1 g of TNT, C7H

Pachacha [2.7K]

Answer: 1g of formaldehyde

Explanation:

Molar Mass of benzene (C6H6) = (12x6) + (6x1) = 78g/mol

1mole(78g) of benzene contains 6.02x10^23 molecules.

1g of benzene with contain = (6.02x10^23) /78 = 7.72x10^21 molecules

Molar Mass of formaldehyde (CH2O) = 12 +2+16 = 30g/mol

1mole (30g) of formaldehyde contains 6.02x10^23 molecules.

1g of formaldehyde will contain = (6.02x10^23) /30 = 2.01x10^22 molecules

Molar Mass of TNT(C7H5N3O6) = (12x7)+(5x1)+(14x3)+(16x6) = 227g/mol

1mole(227g) of TNT contains 6.02x10^23 molecules.

1g of TNT will contain = (6.02x10^23)/227 = 2.65x10^21 molecules

Molar Mass of naphthalene (C10H8) = (12x10) +8 =128g/mol

1mole(128g) of naphthalene contains 6.02x10^23 molecules.

1g of naphthalene will contain = (6.02x10^23)/128 = 4.7x10^21 molecules

Molar Mass of glucose(C6H12O6) = (12x6) + 12 +(16x6) = 180g/mol

1mole(180g) of glucose contains 6.02x10^23 molecules.

1g of glucose will contain = (6.02x10^23)/180 = 3.34x10^21 molecules

Therefore, 1g of each of the compound contains the following:

Benzene = 7.72x10^21 molecules

Formaldehyde = 2.01x10^22 molecules

TNT = 2.65x10^21 molecules

Naphthalene = 4.7x10^21 molecules

Glucose = 3.34x10^21 molecules

From the above, we see clearly that formaldehyde has the largest number of molecules

3 0

3 years ago

uman blood is kept at a typical pH of 7.40 mainly by the carbonic acid–carbonate ion buffer system. The corresponding chemical e

nadya68 [22]

Answer:

The ratio, $\frac{[HCO_{3}^{-}]}{[H_{2}CO_{3}]}$ , is 10.7

Explanation:

$H_{2}CO_{3}$ is an weak acid and $HCO_{3}^{-}$ is it's conjugate base.

So, according to Henderson-Hasselbalch equation, pH of this buffer system can be represented as-

$pH=pK_{a}(H_{2}CO_{3})+log(\frac{[HCO_{3}^{-}]}{[H_{2}CO_{3}]})$

Here pH=7.40, $pK_{a}(H_{2}CO_{3})$ =6.37

So, $7.40=6.37+log(\frac{[HCO_{3}^{-}]}{[H_{2}CO_{3}]})$

or, $\frac{[HCO_{3}^{-}]}{[H_{2}CO_{3}]}=10.7$

So the ratio, $\frac{[HCO_{3}^{-}]}{[H_{2}CO_{3}]}$ , is 10.7

6 0

3 years ago

As you move from right to left on the periodic table the atomic radius _____ Fill in the blank

Alex787 [66]

As you move from right to left on the periodic table the atomic radius decreases

Explanation:

On moving left to right across a period, the atomic number increases.
Due to this the effective nuclear charge also increases.
It implies that the nucleus pull is high for the electrons, due to which the atomic radius decreases.
The diagram is attached below:

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4 years ago

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The inflation of airbags is due to the breakdown of a single chemical substance into two separate substances. Two molecules of s

S_A_V [24]

Answer:

The correct answer is 2 Na atoms

Explanation:

To determine the number of sodium atoms produced in this reaction, the reaction described in the question must be written out in an equation and then balanced

2NaN₃ ⇒ 2Na + 3N₂

From the equation above, it can be deduced that the number of sodium atoms produced in the reaction described in the question is 2

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3 years ago

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