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3 years ago

Which of the following is the best definition of Hess' Law?

1 answer:

7 0

Hess' Law can best be described as A. Heat evolved in a given process can be expressed as the sum of the heats of several processes that, when added, yield the process of interest.

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Why are ionic solids poor conductors of electricity

marshall27 [118]

Answer:

Ionic compounds don't conduct electricity very well because the charge carriers can't move through the crystal. They can conduct heat because the kinetic energy itself is the "heat carrier”.

Hope this helps :)

3 0

3 years ago

Basile [38]

Answer:

The answer of this question is molecule

4 0

3 years ago

The charge on the most stable ion of zinc

Natalija [7]

Zinc (Zn) always has a +2 charge. It is one of the exceptions.

8 0

3 years ago

What is the mass in grams of 0.280 mole sample of sodium hydroxide NaOH

vivado [14]

Answer:

The mass of 0.280 mole sample of sodium hydroxide NaOH is 11.2 grams.

Explanation:

To know the mass in grams of 0.280 moles of sample of sodium hydroxide NaOH, you must know the molar mass of the compound, that is, the mass of one mole of a substance, which can be an element or a compound.

So you know:

Na: 23 g/mole
O: 16 g/mole
H: 1 g/mole

So, the molar mass of NaOH is:

NaOH= 23 g/mole + 16 g/mole+ 1 g/mole= 40 g/mole

Then the following rule of three can be applied: if in 1 mole of sodium hydroxide there are 40 grams, in 0.280 moles how much mass is there?

$mass=\frac{0.28 moles*40 grams}{1 mole}$

mass= 11.2 grams

The mass of 0.280 mole sample of sodium hydroxide NaOH is 11.2 grams.

4 0

3 years ago

A gas sample is held at constant temperature. What happens to the pressure of the sample if the volume is doubled and the number

Iteru [2.4K]

Answer:

If the volume is doubled and the number of molecules is doubled, pressure is unchanged

Explanation:

Step 1: Data given

Temperature = constant

Volume will be doubled

Number of molecules will be doubles

Step 2:

p*V = n*R*T

⇒ gas constant and temperature are constant

Initial pressure = n*R*T / V

Initial pressure = 2*R*T/2

Initial pressure = RT

Final pressure = 4*RT / 4

Final pressure = R*T

If the volume is doubled and the number of molecules is doubled, pressure is unchanged

3 0

2 years ago