HELP ASAP

What are the atomic number and mass number of this atom

lina2011 [118]

No diagram is given therefore I cannot answer however, use this for reference.
The atomic mass of an atom would be the number of protons PLUS the number of neutrons. Because this atom shown has 6 protons and 6 neutrons, they add up to 12. In this case, the atomic mass of this atom is 12. Atomic number is the number of protons in an atom, in this case it is 6. The atomic number is 6.

5 0

3 years ago

The vapor pressure of benzene is 73.03 mm Hg at 25°C. How many grams of estrogen (estradiol), C18H24O2, a nonvolatile, nonelectr

alexira [117]

Answer:

14.9802 grams of estrogen must be added to 216.7 grams of benzene.

Explanation:

The relative lowering of vapor pressure of solution containing non volatile solute is equal to mole fraction of solute.

$\frac{p_o-p_s}{p_o}=\frac{n_2}{n_1+n_2}$

Where:

$p_o$ = Vapor pressure of pure solvent

$p_s$ = Vapor pressure of the solution

$n_1$ = Number of moles of solvent

$n_2$ = Number of moles of solute

$p_o = 73.03 mmHg$

$p_s= 71.61 mmHg$

$n_1=\frac{216.7 g}{78.12 g/mol}=2.7739 mol$

$\frac{73.03 mmHg-71.61 mmHg}{73.03 mmHg}=\frac{n_2}{2.7739 mol+n_2}$

$n_2=0.05499 mol$

Mass of 0.05499 moles of estrogen :

= 0.05499 mol × 272.4 g/mol = 14.9802 g

14.9802 grams of estrogen must be added to 216.7 grams of benzene.

6 0

3 years ago

match the number of negative charges to the number of positive charges to make each combination balanced (see image for answer)

BartSMP [9]

Answer : The correct match is:

1 positive charge = 1 negative charge

2 positive charges = 2 negative charges

3 positive charges = 3 negative charges

Explanation :

As we now that there are three subatomic particles which are protons, electrons and neutrons.

The protons and neutrons are located inside the nucleus and electrons are located around the nucleus.

The protons are positively charged, the electrons are negatively charged and neutrons are neutral.

As we know that all the things are made up of charges and opposite charges attract to each other.

In a neutral atom, the positive charges and negative charges are balanced in an object. That means, in neutral atom the number of positive charges are equal to the negative charges.

So we can say that:

1 positive charge = 1 negative charge

2 positive charges = 2 negative charges

3 positive charges = 3 negative charges

5 0

3 years ago

An atom can be called a particle, but a molecule is never called a particle. True or False ?

ivanzaharov [21]

Answer: False; it contains particles, but that doesn't mean it's a particle itself.

5 0

3 years ago

Caustic soda is 19.1 M NaOH and is diluted for household use. What is the household concentration if 10 mL of the concentrated s

olga nikolaevna [1]

Hello!

To calculate the household concentration of NaOH we need to use the dilution formula, clearing for M2, as you can see in the equation below:

$M1*V1=M2*V2 \\ \\ V2= \frac{M1*V1}{V2}$

Now, we input the values from the data we have onto this equation. M1=19,1 M; V1=10 mL; V2=400 mL, and solve the equation to get the result:

$V2= \frac{M1*V1}{V2}= \frac{19,1M*10mL}{400 mL}=0,48M$

So, the household concentration of NaOH will be 0,48 M

Have a nice day!

4 0

3 years ago