Answer : The number of moles in 369 grams of calcium hydroxide is, 4.98 moles
Explanation : Given,
Mass of calcium hydroxide = 369 g
Molar mass of calcium hydroxide = 74.093 g/mole
Formula used :
Now put all the given values in this formula, we get the moles of calcium hydroxide.
Therefore, the number of moles in 369 grams of calcium hydroxide is, 4.98 moles
Answer:
control.
Explanation:
during an experiment you are required to maintain a separate group of subjects to collect data on so you will be able to make comparisons from your observations. assuming the watered plants grew, what does that mean? they grew at a quicker rate? slower rate? the same rate? compared to what? you need this control group in order to prove your observations either one way or the other such as "compared to unwatered plants, the watered plants grew at *blank* rate."
Answer:
- <u><em>Solution </em></u><em>is a physical combination of one substance dissolved in another.</em>
Explanation:
A <em>solution</em> is a homogeneous mixture.
The solutions are characterized by uniform composition and one phase, but they can be either solid, liquid or gases.
In a solution there is, at least, one solute <em>substance</em> and one or more solvents.
A typical solution is salt and water: salt is the solute, which is <em>dissolved</em>, in water (the solvent).
In a solution, you can not distinguish visually the solute from the solvent, but, since they are physically, and not chemically, combined, they can be separated by physical media, e.g. evaporation.
Alkali metals are rarely found in pure form because they are so reactive.
Alkali metals are in Group 1 of the Periodic Table.
They need to lose only one valence electron to reach a filled valence shell
Thus, they readily react wirh water and other chemicals in the earth to form compounds.
Answer:
Paraffin > Heptadecane > Hexane > 2,2-dimethylbutane > Propane
Explanation:
It must first be establish that all the molecules listed in the question are alkanes. For alkanes, the intermolecular forces between the molecules of alkanes increases with increasing molecular weight. This is as a result of increase in the surface area of the molecule. Increase in surface area implies a greater degree of dispersion forces.
This is the reason why high boiling points are observed for high molecular weight alkanes.