The correct answer is greenhouse gases. It is the most abundant gases among the choices in the atmosphere. These gases are water vapor, methane, nitrous oxide, ozone and carbon dioxide. Without these gases, the temperature of Earth will be about -18 degrees Celsius.
Density of the gas is 3.05 × 10⁻³ g / cm³.
<u>Explanation:</u>
Volume of the cylinder = π r² h
where r is the radius and h is the height of the height or the length of the glass tube.
Here r = 4 cm and h = 27.4 cm
Volume of the cylinder = 3.14 × 4 × 4 × 27.4 = 1376.6 cm³
We have to find the mass of the gas by subtracting the mass of the tube filled with the substance from the mass of the empty tube.
Mass of the substance = 258.5 - 254.3 = 4.2 g
We have to find the density using the formula as,

Plugin the values as,
= 3.05 × 10⁻³ g / cm³
So the Density of the gas is 3.05 × 10⁻³ g / cm³.
Answer:
c.
Explanation:
One of the main differences between an atom and an element is that an atom can be combined but an element cannot be combined. There are many combinations of atoms that make up different gases, liquids, and solids each with a unique makup. For example, water is made up of two hydrogen atoms and one oxygen atom (H20). Elements are made up of only the same type of atom. For example, the element Hydrogen can only contain hydrogen atoms, while the element Carbon can only contain carbon atoms.
Substance change.
solid to a liquid
melting state when heat was applied.
Answer: Conduction is the process by which heat energy is transmitted through collisions between neighboring atoms or molecules. ... The fire's heat causes molecules in the pan to vibrate faster, making it hotter. These vibrating molecules collide with their neighboring molecules, making them also vibrate faster.
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