Under what environmental conditions are you most likely to generate static electricity?

jeyben [28]

Not most elements have DNA, only five "elements" have DNA. The five "elements" are Carbon, Oxygen, Hydrogen, Nitrogen and Phosphorus. Good luck with your question I hope this is what you were looking for.

6 0

3 years ago

"how many grams of calcium are consumed when 156.8 ml of oxygen"

Akimi4 [234]

Your question is incomplete. However, I found a similar problem fromanother website as shown in the attached picture.

To solve this problem, you must know that at STP, the volume for any gas is 22.4 L/mol. So,

Moles O₂: 156.8 mL * 1 L/1000 mL* 1 mol/22.4 L = 0.007 moles
Mass calcium: 0.007 mol O₂ * 2 mol Ca/1 mol O₂ * 40 g/mol Ca = 0.56 g Ca

3 0

3 years ago

Which liquid has the highest vapor pressure at 75°C?

Temka [501]

Answer:

1) Ethanol

Explanation:

If we will have interactions we will need more energy to break them in order to go from liquid to gas. If we need more energy, therefore, the temperature will be higher.

In this case, we can discard the propanone because this molecule don't have the ability to form hydrogen bonds. (Let's remember that to have hydrogen bonds we need to have a hydrogen bond to a heteroatom, O, N, P or S).

Then we have to analyze the hydrogen bonds formed in the other molecules. For ethanol, we will have only 1 hydrogen bond. For water and ethanoic acid, we will have 2 hydrogen bonds, therefore, we can discard the ethanol.

For ethanoic acid, we have 2 intramolecular hydrogen bonds. For water we have 2 intermolecular hydrogen bonds, therefore, the strongest interaction will be in the ethanoic acid.

The closer boiling point to the 75ºC is the ethanol (boiling point of 78.8 ºC) therefore these molecules would have enough energy to break the hydrogen bonds and to past from liquid to gas.