Answer:
Forces between similar molecules are said to be <em>cohesive</em> while those between different types of molecules are said to be <em>adhesive</em>.
Water 'beads' due to its strong <em>cohesive</em> forces. The meniscus of water in a glass tube is <em>concave</em> because the <em>adhesive</em> forces are strong.
Explanation:
The water in a tube has stronger adhesive forces between the water and glass molecules, so the cohesive forces between water molecules are weaker. That makes the water 'ascend' through the tube, giving a concave form of the meniscus. Another example is mercury, which is the opposite. In this case, the cohesive forces are stronger than the adhesive ones, thus the meniscus is convex.
True, biodiversity creates different species animals depend on each other for food and other reasons so the answer is true.
Answer:
8.99×10^-7m
Explanation:
The wavelength can be calculated using the expression below
E=hcλ
Where E= energy= 2.21 x 10^-19 J.
C= speed of light= 3x10^8 m/s
h= planks constant= 6.626 × 10^-34 m2 kg / s
E=hcλ
λ= E/(hc)
Substitute for the values
λ=( 2.21 x 10^-19 )/(6.626 × 10^-34 × 3x10^8 )
= 8.99×10^-7m
Answer:
A
Explanation:
Iron has the ground state electronic configuration [Ar]3d64s2
Fe2+ has the electronic configuration [Ar]3d6.
In an octahedral crystal field, there are two sets of degenerate orbitals; the lower lying three t2g orbitals, and the higher level two degenerate eg orbitals. Strong field ligands cause high octahedral crystal field splitting, there by separating the two sets of degenerate orbitals by a tremendous amount of energy. This energy is much greater than the pairing energy required to pair the six electrons in three degenerate orbitals. Since CN- is a strong field ligand, it leads to pairing of six electrons in three degenerate orbitals
To get the molecular formula we use the individual atomic masses of the atoms making the molecule. Hence, to get the factor by which the empirical formula is multiplied, we divide molar mass by the total of the mass of the atoms making the empirical formula.
(C2H7) the mass of one carbon atoms is 12 so two atoms add up to 24. The mass of one hydrogen atom is 1 a.m.u thus 7 atoms give a total of 7 a.m.u. The sum of the two types of atoms is 24+7= 31
Molar mass=62.18
62.18/31=2.0
Hence, (C2H7) 2=C4H14
