So, we have:
- molecular weight
- shape
- temperature
- kinetic energy
- mass
- density
Let's rule out the different options.
- molecular weight: Say you have a molecule of H2O. H2O can be a solid, liquid, or gas, but its molecular weight never changes throughout (It's still the same molecule, no matter what phase it is in). We can rule this out.
- shape: Let's pretend we have three identical closed containers, and we fill each one halfway with water, blocks of ice cubes, and water vapor. In the container with water, you will see that the water takes the shape of the container, but doesn't fill the entire container up. The ice cubes will stay ice cubes, assuming they don't melt, so they don't take the shape of the container. The vapor will fill up the entire container. Since all three are different, I would say yes, this could be a distinguishable feature.
- temperature: In general, I would say no, because every element/molecule has different boiling points and different vaporization points. So if you have a liquid at 5°C, you could also have a different element in solid form at 5°C. But if you're comparing a single type of molecule, it would have a boiling point and a vaporization point, so you <em>would</em> be able to tell between them.
- kinetic energy: Kinetic energy refers to how much movement there is in respect to each molecule. In solids, the molecules are packed tightly together and can't move very much, so they have lower kinetic energy. In liquids, they are less packed, but still restricted. And in gases, they can fly freely, so they will have much more kinetic energy than liquids or solids. This one's a yes.
- mass: No matter what form, there are still the same amount of molecules, and each molecule has the same mass as before. It won't change.
- density: Since the molecules are more spread out in gases, it will be less dense. Liquids will be more dense, and solids will have the greatest density. So, yes.
Conclusion: shape, kinetic energy, density, (and temperature if it's talking about a single type of molecule)
<span>A small proportion of helium in the crust is helium that was trapped in the Earth when the Earth formed and has not yet escaped. Most helium on Earth, however, forms as a result of alpha decay of uranium and thorium. The emitted alpha particles, once they grab a couple of stray electrons, become helium atoms and can accumulate in gas reservoirs along with things such as methane.</span>
Answer:a) 0.1 mole. b) 4g. c) 2% d) 196 mL
Explanation: in 200mL , 0.1mole
mw NaOH = 40g/mol —> 4g in 0.1 mole
4g in 200mL so 2g in 100mL
density NaOH = 1g/mL so if 4g in 200 mL, 4mL , 196 mL water
Answer:
Attractions between molecules cause a reduction in volume
Explanation:
Answer:
2,760 grams NaCl
Explanation:
To find grams of NaCl, you need to (1) convert moles of Na to moles of NaCl (via mole-to-mole ratio from reaction) and (2) convert moles of NaCl to grams (via molar mass from periodic table). The final answer should have 3 significant figures based on the given measurement.
2 Na + Cl₂ --> 2 NaCl
Molar Mass (NaCl) = 22.99 g/mol + 35.45 g/mol
Molar Mass (NaCl) = 58.44 g/mol
47.2 moles Na 2 moles NaCl 58.44 grams
---------------------- x --------------------------- x ------------------------- =
2 moles Na 1 mole NaCl
= 2,758.368 grams NaCl
= 2,760 grams NaCl
