Which chemical reaction involves the fewest oxygen atoms?

A certain radioactive atom has 90 protons and 142 neutrons. If this atom undergoes alpha decay, what is the mass number of the d

Hatshy [7]

Answer: the mass number of the daugther atom is 232,

Explanation:

1) Alpha (α) decay is a nuclear reaction in which a nucleus (parent's nucleus) emits an alpha (α) particle and leads to a different atom (daughter atom).

2) The alpha (α) particle is a nucleus of helium atom, i,e, a nucleus with two protons and two neutrons. The symbol used for the α particles is ⁴₂He, where the superscript 4 indicates the mass number (2 protons + 2 neutrons = mass number 4), and the subscript 2 indicates the atomic number (number of protons).

3) Then, to determine the mass number of the daughter atom you just need to do a mass number balance:

mass number of the parent atom = mass number of the daugther atom + mass number of the α particle.

The mass number of the radioactive (parent) atom is 90 protons + 142 neutrons = 232.

∴ 232 = x + 4 ⇒ x = 232 - 4 = 228 ← answer.

The full equation may help you to have a wider vision of the problem:

²³²₉₀ X → ⁴₂ He + ²²⁸₈₈ Y

Note this:

232 = 4 + 228 (this is a mass number balance)
90 = 2 + 88 (this is an atomic number balance)
X is the parent atom, and Y is the daughter atom
You can use a periodic table to determine the identity of the unknown atoms (using the atomic numbers).

5 0

2 years ago

Read 2 more answers

Dr. Franck cuts a bar of pure gold into smaller and smaller pieces. Will this action change the element that makes up the bar? E

Anvisha [2.4K]

Answer:

i believe this is a chemical or physical question? well your answer to that is no the element does not change because the gold is still gold it is still physical because you have just cut it into piece it is still gold

Explanation:

lmk if it was helpful :/

7 0

1 year ago

A tank of oxygen has a volume of 40.0L and is held at a pressure of 159atm at 25∘C. What volume of O2 gas (in liters) would ther

Advocard [28]

Answer:

V2 = 6616 L

Explanation:

From the question;

Initial volume = 40L

Initial Pressure, P1 = 159atm

Initial Temperature T1 = 25 + 273 = 298K (Upon converting to Kelvin unit)

Final Volume, V2 = ?

Final Pressure, P2 = 1 atm

Final Temperature T2 = 37 + 273= 310K (Upon converting to Kelvin unit)

These quantities are related by the equation;

P1V1 / T1 = P2V2 / T2

V2 = T2 * P1 * V1 / T1 * P2

V2 = 310 * 159 * 40 / (298 * 1)

V2 = 6616 L

6 0

1 year ago

Which balanced redox reaction is occurring in the voltaic cell represented by the notation of A l ( s ) | A l 3 ( a q ) | | P b

frez [133]

The question is missing. Here is the complete question.

Which balanced redox reaction is ocurring in the voltaic cell represented by the notation of $Al_{(s)}|Al^{3+}_{(aq)}||Pb^{2+}_{(aq)}|Pb_{(s)}$ ?

(a) $Al_{(s)}+Pb^{2+}_{(aq)} ->Al^{3+}_{(aq)}+Pb_{(s)}$

(b) $2Al^{3+}_{(aq)}+3Pb_{(s)} -> 2Al_{(s)}+3Pb^{2+}_{(aq)}$

(c) $Al^{3+}_{(aq)}+Pb_{(s)} ->Al_{(s)}+Pb^{2+}_{(aq)}$

(d) $2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}$

Answer: (d) $2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}$

Explanation: Redox Reaction is an oxidation-reduction reaction that happens in the reagents. In this type of reaction, reagent changes its oxidation state: when it loses an electron, oxidation state increases, so it is oxidized; when receives an electron, oxidation state decreases, then it is reduced.

Redox reactions can be represented in shorthand form called cell notation, formed by: left side of the salt bridge (||), which is always the anode, i.e., its half-equation is as an oxidation and right side, which is always the cathode, i.e., its half-equation is always a reduction.

For the cell notation: $Al_{(s)}|Al^{3+}_{(aq)}||Pb^{2+}_{(aq)}|Pb_{(s)}$

Aluminum's half-equation is oxidation:

$Al_{(s)} -> Al^{3+}_{(aq)}+3e^{-}$

For Lead, half-equation is reduction:

$Pb^{2+}_{(aq)}+2e^{-} -> Pb_{(s)}$

Multiply first half-equation for 2 and second half-equation by 3:

$2Al_{(s)} -> 2Al^{3+}_{(aq)}+6e^{-}$

$3Pb^{2+}_{(aq)}+6e^{-} -> 3Pb_{(s)}$

Adding them:

$2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}$

The balanced redox reaction with cell notation $Al_{(s)}|Al^{3+}_{(aq)}||Pb^{2+}_{(aq)}|Pb_{(s)}$ is

$2Al_{(s)}+3Pb^{2+}_{(aq)} -> 2Al^{3+}_{(aq)}+3Pb_{(s)}$

6 0

2 years ago

1. Which liquid sample is a pure substance?

IRISSAK [1]

The whole Activity , poem and paragraph is missing in the question.

Answer:

(1) Liquid A

(2) Solid A

Explanation:

Using this part of the given poem

Substances and mixtures behave differently,

During boiling and melting most especially

Boiling point of substance is fixed while mixture is not

Substance melts completely but mixture does not

The boiling point of the Pure substance remain fixed after reaching its boiling point this is shown by Liquid A

Solid A is melting completely so Solid A is a pure substance.

6 0

1 year ago