The most common method astronomers use to determine the composition of stars, planets, and other objects is spectroscopy. This process utilizes instruments with a grating that spreads out the light from an object by wavelength. This spread-out light is called a spectrum. Every element has a unique fingerprint that allows researchers to determine what it is made of.
The fingerprint often appears as the absorption of light. Every atom has electrons, and these electrons like to stay in their lowest-energy levels. But when photons carrying energy hit an electron, they can push it to higher energy levels. This is absorption, and each element’s electrons absorb light at specific wavelengths related to the difference between energy levels in that atom. But the electrons want to return to their original levels, so they don’t hold onto the energy for long. When they emit the energy, they release photons with exactly the same wavelengths of light that were absorbed in the first place. An electron can release this light in any direction, so most of the light is emitted in directions away from our line of sight. Therefore, a dark line appears in the spectrum at that particular wavelength.
Because the wavelengths at which absorption lines occur are unique for each element, astronomers can measure the position of the lines to determine which elements are present in a target. The amount of light that is absorbed can also provide information about how much of each element is present.
D) The broadest group of organization is known as the domain.
Answer:
2.75 mol
Explanation:
Given data:
Mass of Nitrogen = 38.5 g
Moles of ammonia produced = ?
Solution:
Chemical equation:
N₂ + 3H₂ → 2NH₃
Number of moles of nitrogen:
Number of moles = mass/ molar mass
Number of moles = 38.5 g/ 28 g/mol
Number of moles = 1.375 mol
Now we will compare the moles of ammonia and nitrogen from balance chemical equation.
N₂ : NH₃
1 : 2
1.375 : 2×1.375 = 2.75 mol
Thus 2.75 moles of ammonia are produced from 38.5 g of nitrogen.
Answer:
The volume will also decrease.
Explanation:
This illustration clearly indicates Boyle's law.
Boyle's law states that the volume of a fixed mass of gas is directly proportional to the absolute temperature, provided the pressure remains constant. Mathematically, it is represented as:
V & T
V = KT
K = V/T
V1/T1 = V2/T2 =... = Vn/Tn
Where:
T1 and T2 are the initial and final temperature respectively, measured in Kelvin.
V1 and V2 are the initial and final volume of the gas respectively.
From the illustration above, the volume is directly proportional to the temperature. This implies that as the temperature increases, the volume will also increase and as the temperature decreases, the volume also will decrease.
