If the atomic number of an atom is 4 and the mass number is 9, then how many electrons does it have

1 answer:

5 0

The atomic number of an atom says how many protons it has. This number cant change, since the atomic number is what gives elements their identities (in the periodic table, at least).
The mass number, on the other hand, says how many protons AND neutrons the atom has (so, the sum of P+ and N0). So, electrons have nothing to do with this number.
Atoms are neutrally charged, which means there has to be an equal number of positive and negative particles. The negative particles of an atom are its electrons, and since our atom has 4 protons, it must also have 4 electrons.

You might be interested in

If you have an effusive personality, then it __________ of you. motor oil will __________ across the gravel if it spills out of

erica [24]

The first answer in the blank is pours out of you, the second answer in the space provided is diffuse. It is because a person who has an effusive personality will likely pour out his or her emotions while the motor oil will likely diffuse if this has been spilled out of the can.

6 0

3 years ago

WILL GIVE BRILLIANTIST

sleet_krkn [62]

Answer: A. foliated

Explanation: took the test!

7 0

2 years ago

Read 2 more answers

A Porsche sports car can accelerate at 8.8 m/s^2. Determine its acceleration in km/h^2.

finlep [7]

Answer:

The acceleration expressed in the new units is $114.048 Km/h^{2}$

Explanation:

To convert from $m/s^{2}$ to $Km/h^{2}$ it is necessary to remember that there are 1000 meters in 1 kilometer and 3600 seconds in 1 hour:

Then by means of a rule of three it is get:

$8.8\frac{m}{s^{2}}.(\frac{1Km}{1000m}).(\frac{3600s}{1h})^{2}$

$8.8\frac{m}{s^{2}}.(\frac{1Km}{1000m}).(\frac{12960000s^{2}}{1h^{2}})$

Hence, the units of meters and seconds will cancel. Notice the importance of square the ratio 3600s/1h, so that way they can match with the other units:

$114.048 Km/h^2$