All categories

3 years ago

The atomic number of lithium is 3. How many neutrons does an atom of lithium have if it is represented by the symbol shown below

Chemistry

2 answers:

Nataly [62]3 years ago

7 0

The answer is 4 neutrons
Hope this helped!

Luba_88 [7]3 years ago

5 0

Answer:

Lithium has 4 neutrons

Explanation:

The number shown above the lithium symbol (Li) is the mass number.

The mass number (A) represents the protons and neutrons an atom has.

The atomic number(Z) in the other hand represents the protons only.

So, the difference between this two numbers is the amount of neutrons.

$n_{neutrons}=A-Z=7-3=4$

You might be interested in

What is the main difference in covalent bonds in diatomic chlorine and diatomic oxygen? diatomic means two atoms of the same typ

Aneli [31]

The correct response is C. Chlorine forms 1 covalent bond while Oxygen forms 2 covalent bonds.

3 0

3 years ago

If hydrofluoric acid is a stronger acid than acetic acid, which statement is most likely true?

Alchen [17]

Answer: The statement conjugate base of hydrofluoric acid is weaker than that of acetic acid is most likely true.

Explanation:

A strong acid upon dissociation gives a weak conjugate base. This can also be said as stronger is the acid, weaker will be its conjugate base or vice-versa.

Hydrofluoric acid is a strong base as it dissociates completely when dissolved in water.

For example, $HF \rightleftharpoons H^{+} + F^{-}$

The conjugate base is $F^{-}$ which is a weak base.

Acetic acid is a weak acid as it dissociates partially when dissolved in water. So, the conjugate base of acetic acid is a strong base.

$CH_{3}COOH \rightarrow CH_{3}COO^{-} + H^{+}$

Thus, we can conclude that the statement conjugate base of hydrofluoric acid is weaker than that of acetic acid is most likely true.

4 0

3 years ago

Using only the 1h nmr spectrum of the crude nitration product, determine if the product is mostly ortho-, meta-, or para- substi

tatiyna

The nitartion of methyl benzoate is expected to proceed as given in the equation below:

In methyl benzoate there are 3 types of 1 H proton. The two ortho to the C=O group is a doublet at 8 ppm the 2 metal to the C=O is a multiple at 7.5 ppm and one para to the C=O is a multiplet at 7.5 ppm.

On nitration the ortho will probably show two signal one being a single with 3 proton integration and one a doublet with 1 H integration

The meta will show a highly down field singlet (coresponding to 1 proton), two unequal doublets (corresponding to 1 H each) and one multiplets (corresponding to 1H). This is the major product as seen from the 1H NMR.

The para isomer will come as two doublets which will be very close to each other there is a small signal for this set between 8.2 and 8.3 ppm.

7 0

3 years ago

Wine goes bad soon after opening because the ethanol CH3CH2OH dissolved in it reacts with oxygen O2 gas to form water and aqueou

bagirrra123 [75]

Answer:

We need 0.095 moles of ethanol

Explanation:

Step 1: Data given

Number of moles water = 0.095 moles

Step 2: The balanced equation

CH3CH2OH + O2 ⇒ H2O + CH3COOH

Step 3: Calculate moles of ethanol

For 1 mol ethanol we need 1 mol oxygen to produce 1 mol water and 1 mol acetic acid

For 0.095 moles water, we need 0.095 moles ethanol and 0.095 moles oxygen

We need 0.095 moles of ethanol

5 0

3 years ago

Two samples of sodium chloride with different masses were decomposed into their constituent elements. One sample produced 2.55 g

Charra [1.4K]

Answer:

4.71 g of sodium and 7.25 g of chlorine

Explanation:

Note: The question is incomplete. the complete question is given below:

Two samples of sodium chloride with different masses were decomposed into their constituent elements. One sample produced 2.55 g of sodium and 3.93 g of chlorine. Being consistent with the law of constant composition, also called the law of definite proportions or law of definite composition, which set of masses could be the result of the decomposition of the other sample?

4.71 g of sodium and 3.30 g of chlorine

4.71 g of sodium and 7.25 g of chlorine

4.71 g of sodium and 1.31 g of chlorine

4.71 g of sodium and 13.7 g of chlorine

The law of definite proportions states that all pure samples of a particular chemical compound contain the same elements combined in the same proportion by mass.

This means that irrespective of the source of any sample of a pure chemical compound, the constituents elements are always combined in the same mass ratio.

In the first sample, the mass ratio of Sodium to chlorine is given below:

mass of sodium = 2.55 g

mass of chlorine = 3.93 g

mass ratio; sodium to chlorine = 2.55 / 3.93 = 0.65

From the set of masses give above, we can determine the result of the decomposition of the second sample.

4.71 g of sodium and 3.30 g of chlorine

mass ratio; sodium to chlorine = 4.71 / 3.30 = 1.43

4.71 g of sodium and 7.25 g of chlorine

mass ratio; sodium to chlorine = 4.71 / 7.25 = 0.65

4.71 g of sodium and 1.31 g of chlorine

mass ratio; sodium to chlorine = 4.71 / 1.31 = 3.59

4.71 g of sodium and 13.7 g of chlorine

mass ratio; sodium to chlorine = 4.71 / 13.7 = 0.34

From the results above, the correct set of masses for the second sample is 4.71 g of sodium and 7.25 g of chlorine

3 0

2 years ago