Answer:
Conduction is the transfer of thermal energy through direct contact. Convection is the transfer of thermal energy through the movement of a liquid or gas. Radiation is the transfer of thermal energy through thermal emission.
Answer:
C. It blocked out sunlight
Explanation:
The asteroid impact 65 million years ago was devastating for lot of the animals and plants, resulting in a mass extinction, most noticeably of the dinosaurs. The impact itself killed a lot of flora and fauna, but it was the effect afterward that was crucial. From this impact, there was so much debris propelled into the atmosphere that the sunlight got blocked. Once this happened, most of the plants died out as they were not able to perform photosynthesis. Because the plants were dying out, the herbivores were left without food, so soon they followed, and because the herbivores died out, the predators died out to because they were left without food. The winners turned out to be the small and not specialized plants and animals.
Answer:
A polar molecule has both a partial positive and a partial negative. Since NaCl (sodium chloride) is made out of Na+ and Cl- ions, the positive and negative parts of the water will pull on these ions individually since positive attracts negative and negative attracts positive. This magnetic force causes the Na+ and the Cl- ions to be pulled apart.
Explanation:
Answer: The density of chloroform is 1.47 g/mL
Explanation : Given,
Volume = 40.5 mL
Mass of cylinder = 85.16 g
Mass of cylinder and liquid = 145.10 g
First we have to calculate the mass of liquid (chloroform).
Mass of liquid = Mass of cylinder and liquid - Mass of cylinder
Mass of liquid = 145.10 g - 85.6 g
Mass of liquid = 59.5 g
Now we have to calculate the density of liquid (chloroform).
Formula used:

Now putting g all the given values in this formula, we get:


Therefore, the density of chloroform is 1.47 g/mL
If a piece of charcoal is taken and set on fire it will evolve CO2 and heat. Charcoal is solid but carbon dioxide is gaseous. This is an example of change of state and evolve of heat during chemical reaction.