Equations Topic 10/11

Question 1

Index of Hydrogen Deficiency (chapter 10)

Answer 1

IHD = (2C + 2) + N - H - X / 2

where
C = number of carbon atoms
N = number of nitrogen atoms
H = number of hydrogen atoms
X = number of halogen atoms

Question 2

Propagation of uncertainties: for addition and subtraction such as C = A +- B

Answer 2

ΔC = ΔA + ΔB

where
ΔA = absolute uncertainty in A

Question 3

Propagation of uncertainties: for multiplication and division such as C = A x B or C = A / B

Answer 3

ΔC / C = ΔA / A + ΔB / B

where
ΔA = absolute uncertainty in A

Question 4

Propagation of uncertainties: for exponents such as C = A^n

Answer 4

ΔC / C = n (ΔA / A)

where
ΔA = absolute uncertainty in A
n = exponent

Question 5

Index of Hydrogen Deficiency (chapter 11)

Answer 5

CxHy

IHD = ( 2x + 2 - y) / 2

**ignore O, S
**count halogens as H
**N, add 1 to C and 1 to H

Question 6

Bragg equation (chapter 11)

Answer 6

nλ = 2dsinθ

d = distance between the planes, also the diameter of the atom
λ = wavelength

Question 7

Speed of light

Answer 7

c = fλ