Electronegativity
The tendency of an atom to pull electrons towards itself is called electronegativity.
It is the tendency of an atom to attract bonding pair of electrons towards itself. These atoms which are more electronegative are able to bear a negative charge and be stable.
Unlike electropositive elements which tend to lose electrons , electronegative elements hold on tightly to the electrons.
The electronegativity is measured using the Pauling Scale where the most electronegative element of the periodic table, Fluorine , is given a value of 4 and the rest of the elements have values lower than 4 according to the trends followed by their groups and periods.
The least electronegative element of the periodic table , Cesium has a value of 0.7 on the Pauling Scale.
Electronegativity increases when we move from left to right in the periodic table and it decreases (in general) when we move down the group.
(To know more about Electronegativity: https://brainly.in/question/5742635 )
Answer:
Explanation:
Using at least three sentences,, explain the four stages involved in genetic engineering/gene cloning.
Stage 1: Isolation of the target gene
Stage 2: Insertation of the target gene
Stage 3: Introduction of the vector into a host
Stage 4: Amplification of the target gene by the host cell and screening
Answer: Molarity is defined as moles of solute per liter of solution. So, find the moles of solute and divide by the liters of solution.
molar mass AlCl3 = 133g/mole
moles AlCl3 = 127 g x 1 mole/133 g = 0.955 moles
liters of solution = 400 ml x 1 liter/1000 ml = 0.400 liters
Molarity = 0.955 moles/0.400 liters = 2.39 M
Explain: I looked it up on wyzant.com
Given the balanced equation:
( Reaction type : double replacement)
CaF2 + H2SO4 → CaSO4 + 2HFI
We can determine the number of grams prepared from the quantity of 75.0 H2SO4, and 63.0g of CaF2 by converting these grams to moles per substance.
This can be done by evaluating the atomic mass of each element of the substance, and totaling it to find the molecular mass.
For H2SO4 or hydrogen sulfate it's molecular mass is the sum of the quantity of atomic mass per element. H×2 + S×1 + O×4 = ≈1.01×2 + ≈32.06×1 + ≈16×4 = 2.02 + 32.06 + 64 = 98.08 u (Dalton's or Da) or g / mol.
For CaF2 or calcium fluoride, it's molecular mass adds 1 atomic mass of calcium and 2 atomic masses of fluoride due to the number of atoms.
Ca×1 + F×2 = ≈40.07×1 + ≈19×2 = 40.08 + 38 = 78.07 u (Da or Dalton's) or g / mol.
