What is the correct classification of a mixture in which both a solid and liquid are visible?

He distance from Earth to the North Star is about 430 light-years. Which of the following statements describes why scientists us

garri49 [273]

Answer:

D

Explanation:

because the rest don’t make any sense

8 0

2 years ago

What are the number if protons, neutrons, and electrons

marishachu [46]

protons and electrons are both always the atomic number which is 9 in this case.

For neutrons you subtract the atomic number (9) from the weight of the atom (18.998) some teachers will want you to round to the nearest whole (19). We do this because the number of protons is the atomic number so if you subtract the protons from the whole weight of the atom you would have the electrons and neutrons left. Since electrons weigh so little we don't have to subtract them. Weighing neutrons and electrons would be like weighing an elephant (neutrons) and then putting one marshmallow on the scale (electron).

5 0

3 years ago

What is the solubility of argon (in units of grams per liter) in water at 25 °C, when the Ar gas over the solution has a partial

beks73 [17]

Answer:

0.02405 g/L is the solubility of argon in water at 25 °C.

Explanation:

Henry's law states that the amount of gas dissolved or molar solubility of gas is directly proportional to the partial pressure of the liquid.

To calculate the molar solubility, we use the equation given by Henry's law, which is:

$C_{Ar}=K_H\times p_{gas}$

where,

$K_H$ = Henry's constant = $1.40\times 10^{-3}mol/L.atm$

$p_{Ar}$ = partial pressure of carbonated drink = 0.51atm

Putting values in above equation, we get:

$C_{Ar}=1.40\times 10^{-3}mol/L.atm\times 0.430 atm\\\\C_{Ar}=6.02\times 10^{-4}mol/L$

Molar mass of argon = 39.95 g/mol

Solubility of the argon gas :

$6.02\times 10^{-4}mol/L\times 39.95 g/mol=0.02405 g/L$

0.02405 g/L is the solubility of argon in water at 25 °C.

5 0

3 years ago

Homeostasis subheading The maintenance of stable internal conditions is called

melamori03 [73]

Answer:

<h3>homeostasis</h3>

•the maintenance of a stable internal environment

Hope this helps :)

6 0

3 years ago

. Write the balanced equation, then outline the steps necessary to determine the information requested in each of the following:

mafiozo [28]

Answer:

See explanation

Explanation:

a) The equation of the reaction is;

2Na + Cl2 ------>2NaCl

Number of moles of sodium = 10g/23 g/mol = 0.43 moles

If 2 moles of sodium reacts with 1 mole of Cl2

0.43 moles reacts with 0.43 * 1/2 = 0.215 moles of Cl2

Mass = 0.215 moles of Cl2 *71 g/mol = 15.265 g

b) Equation of the reaction;

HgO -> Hg + O2

1.252 moles of HgO 1.252/32 gmol = 0.039 moles

1 mole of HgO yields 1 mole of oxygen hence

0.039 moles of HgO yields 0.039 moles of oxygen

Mass of oxygen = 0.039 moles * 32 g/mol = 1.248 g

c) Equation of the reaction;

2NaNO3 -----> 2NaNO2 + O2

Number of moles of 128 g of oxygen = 128g/32 g/mol = 4 moles

2 moles of NaNO3 yields 1 mole of oxygen

x moles of NaNO3 yields 4 moles of oxygen

x = 8 moles of NaNo3

Mass of NaNO3 = 8 * 85 g/mol = 680 g of NaNo3

6 0

2 years ago