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Why does ionization energy increase across a period?

First of all, let's define ionization energy. Ionization energy is the energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms. The higher this energy is, the harder it is to remove t...

Answered by Amelia F. • Chemistry tutor

27933 Views

Expand (x-3)(x+7)

FOIL Method: F - First xx = x² O - Outside x7=7x I - Inside -3x=-3x L - Last -37= -21 Add all the results up to get the answer: x²+7x-3x-21 = x²

Answered by Martin L. • Maths tutor

7339 Views

Find the value of x: 2x^2 - 3x - 4 = 1

2x^2 - 3x - 4 = 1
To solve, we should bring all the terms to one side, and equate the equation to 0. To do this, we should subtract 1 from each side.
2x^2 - 3x - 4 - 1 = 1 - 12x^2 - 3x - 5 = 0

Answered by Prithvie S. • Maths tutor

3945 Views

Why does magnesium have a higher melting point than sodium?

Both sodium and magnesium have metallic bonding between atoms. Outer electrons become delocalised and float freely between the positive ions. The positive ions attract the negatively charged electrons so ...

Answered by Suzie C. • Chemistry tutor

40998 Views

How does temperature affect rate of reaction of an enzyme controlled reaction?

An increase in temperature increases kinetic energy of particles, so collision frequency increases and more enzyme-substrate complexes are formed, therefore rate of reaction increases. The rate of reactio...

Answered by Suzie C. • Biology tutor

12650 Views