All categories

2 years ago

When an alpha particle is emitted from an unstable nucleus, the atomic mass numberof the nucleus

Chemistry

1 answer:

barxatty [35]2 years ago

3 0

Answer:

The correct option is D.

Explanation:

Radioactive substances usually emit different types of particles when they are decaying. Such particles include alpha particles, beta particles and gamma ray. When an alpha particle is emitted from an unstable radioactive nucleus such nucleus usually lost an atomic mass that correspond to that of helium atom. Note that an alpha particle is made up of two protons and two neutrons, which result in mass number of 4. Thus, a nucleus that emit an alpha particle will have its mass number (atomic mass) reduce by 4 and atomic number that is reduced by 2.

You might be interested in

Commercially available hot packs are simple in design: a pouch with water on one side, isolated by a barrier from a specific sal

liq [111]

Answer:

b :)

Explanation:

an exothermic reaction is when heat/light is produced. heart is produced from this reaction so it is exothermic

3 0

2 years ago

From the Bohr equation in the introduction, the calculated energy of an electron in the sixth Bohr orbit of a hydrogen atom is

Natalka [10]

Answer:

= - 0.38 eV

Explanation:

Using Bohr's equation for the energy of an electron in the nth orbital,

E = -13.6 $\frac{Z^{2} }{n^{2} }$

Where E = energy level in electron volt (eV)

Z = atomic number of atom

n = principal state

Given that n = 6

⇒ E = -13.6 × $\frac{1^{2} }{6^{2} }$

= - 0.38 eV

Hope this was helpful.

4 0

2 years ago

Equation: 3Cu(s) 8HNO3(aq) --> 2NO(g) 3Cu(NO3)2(aq) 4H2O(l) In the above reaction, the element oxidized is ______, the reduci

igomit [66]

Answer:

1. Cu

2. Cu

3. 2 electrons.

Explanation:

Step 1:

The equation for the reaction is given below:

3Cu(s) + 8HNO3(aq) -> 2NO(g) 3Cu(NO3)2(aq) + 4H2O(l)

Step 2:

Determination of the change of oxidation number of each element present.

For Cu:

Cu = 0 (ground state)

Cu(NO3)2 = 0

Cu + 2( N + 3O) = 0

Cu + 2(5 + (3 x -2)) =0

Cu + 2 (5 - 6) = 0

Cu + 2(-1) = 0

Cu - 2 = 0

Cu = 2

The oxidation number of Cu changed from 0 to +2

For N:

HNO3 = 0

H + N + 3O = 0

1 + N + (3 x - 2) = 0

1 + N - 6 = 0

N = 6 - 1

N = 5

NO = 0

N - 2 = 0

N = 2

The oxidation number of N changed from +5 to +2

The oxidation number of oxygen and hydrogen remains the same.

Note:

1. The oxidation number of Hydrogen is always +1 except in hydride where it is - 1

2. The oxidation number of oxygen is always - 2 except in peroxide where it is - 1

Step 3:

Answers to the questions given above

From the above illustration,

1. Cu is oxidize because its oxidation number increased from 0 to +2 as it loses electron.

2. Cu is the reducing agent because it reduces the oxidation number of N from +5 to +2.

3. The reducing agent i.e Cu transferred 2 electrons to the oxidising agent HNO3 because its oxidation number increase from 0 to +2 as it loses its electrons. This means that Cu transfer 2 electrons.

7 0

2 years ago

Which statement regarding serum magnesium (Mg ++) is true? (Select all that apply.) Alcohol-related diseases frequently cause lo

Elanso [62]

Answer:

Alcohol-related diseases frequently cause low Mg+ levels.

- Mg+ deficiencies must be treated before potassium (K+) deficiencies.

- Mg+ deficiencies often result in low serum potassium (K+)

- Mg++ levels present similarly to calcium (Ca++) levels in the blood.

- Vomiting is not generally seen as a major cause of Mg+ loss

3 0

2 years ago

What element is used in bright flashing advertising signs

Sergeu [11.5K]

The element used in advertising signs is neon.

4 0

2 years ago