Answer:
Covalent bonds usually occur between nonmetals. For example, in water (H2O) each hydrogen (H) and oxygen (O) share a pair of electrons to make a molecule of two hydrogen atoms single bonded to a single oxygen atom. ... Covalent compounds tend to be soft, and have relatively low melting and boiling points.
Answer:
The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
Explanation:
Where:
Q = heat absorbed or heat lost
c = specific heat of substance
m = Mass of the substance
ΔT = change in temperature of the substance
We have mass of copper = m = 25.3 g
Specific heat of copper = c = 0.385 J/g°C
ΔT = 39°C - 22°C = 17°C
Heat absorbed by the copper :
The heat needed to warm 25.3 g of copper from 22°C to 39°C is 165.59 Joules.
<span>1.86 moles of hydrogen gas.
Since what the HCl is reacting with hasn't been mentioned, I'll assume zine. In that case, the balanced reaction is
Zn + 2HCl ==> ZnCl2 + H2
So for every 2 moles of HCl used, 1 mole of hydrogen gas will be generated. So let's figure out how many moles of HCl we have and then divide by 2.
Molarity is defined as moles/liter. So a 2.75 M HCl solution has 2.75 moles of HCl per liter. So the total number of moles we have is:
2.75 mole/L * 1.35 L = 3.7125 mol
And since we get 1 mole H2 per mole of HCl, we get:
3.7125 mol / 2 = 1.85625 mol
Rounding to 3 significant figures gives us 1.86 moles of hydrogen gas.</span>
Answer:
The liquid boils.
Explanation:
Vapor pressure is simply defined as the pressure exerted on a substance (solid/liquid) by the vapor of the substance collected just at the top of the surface of the substance. In concise words, it is the pressure of Vapor that is in contact with its solid or liquid state.
For a liquid, it is the pressure of the Vapor gathering at the top of the surface of the liquid.
When this Vapor pressure matches the external pressure, the temperature stays constant and the molecules of the liquid all through the liquid can gain enough energy, rise to the surface of the liquid and break free in gaseous form; thereby, boiling.
The definition of boiling point basically explains that it is the point at which temperature stays constant, and the vapour pressure of the liquid matches the atmospheric/external pressure around the liquid and its liquid molecules change into vapor.
This is why liquids boil faster at higher altitudes; the atmospheric pressure at higher altitudes is reduced, hence, the temperature at which liquid boils at this high altitude is normally lower than its known boiling point temperature.
It is also why food cooks to a temperature higher than the boiling point of water in a pressure cooker/pot. The added pressure ensures that the cooking water boils at temperatures higher than its boiling point; thereby exposing the cooking ingredients to a higher temperature, leading to faster cooking.
Hence, it is obvious why boiling is the answer to this question.
