The term defined as the change in direction of light when it goes from one medium into a different medium is refraction.
Refraction is the change of direction on the propagation of a beam of light when it passes from a medium to other; this only happens when the light travels at different speeds in both media.
When a beam of light that travels in the air incedes in a slab of glass, part of the beam is reflected (bounces) and part is refracted (it penetrates in the glass and changes the angle).
Also,due to the different speeds of light in air and water, when a beam of light passes from air to water, it refracts.
Answer:
C.ratio of elements in the compound.
Explanation:
A compound is a substance that constitutes two or more elements in a defined proportion. A chemical compound is different from another compound in what it contains i.e. elements. A chemical formula shows the elements contained in a specific compound. For example, the chemical formula of sodium chloride (NaCl) shows us that it contains Sodium (Na) and Chlorine (Cl) elements as represented by symbols.
In addition to this, a chemical formula also shows the ratio of each element that makes up the compound. An element can have more than one atom in a compound. For example, CaCl2 is the chemical formula for Calcium chloride and it shows is that the ratio of Calcium (Ca) to Chlorine (Cl) is 1:2.
Okay
Mr (H2O)= 18g
therefore moles of H2O
is 720.8/18= 40.04mol
the ratio of H2 to O2 to H2O is
2 : 1 : 2
so moles of H2 is same as H2O here
H2= 40.04moles
moles of O2 is half
so 40.04 x 0.5
20.02moles
grams of O2 is
its moles into Mr of O2
that's 20.02 x 32 = 640.64g
Answer:
1s2 2s2 2p6
Explanation:
The nitride ion(N^3-) is formed when nitrogen gains three electrons. Nitrogen possesses seven electrons in its orbitals and ordinarily has the electronic configuration; 1s2 2s2 2p3. However,being in group 15, nitrogen can accept three electrons to form the nitride ion and complete its octet of electrons. When this happens, three electrons are added to the nitrogen atom and the electronic configuration is now the same as that of Neon, its closest noble gas which is 1s2 2s2 2p6. Hence the answer given above.
Elements can accept or donate electrons in order to complete their octet structure in accordance to the octet rule which states that atoms and ions must possess eight electrons in their outermost shell in order to attain chemical stability. The reason for ion formation and chemical reaction is in order for species to attain the octet structure.
