General Chemistry Unit R

Why are significant figures important in measurements and calculations?

They reflect the true precision of the measurement tool and they keep calculations consistent to maintaint the correct level of precision.

Conversion °F to °C

°C= 5/9(°F−32)

Conversion °K to °C

°C= °K − 273.15

Conversion °C to °F

°F = (°C x 9/5) +32

Conversion °F to °K

°K= 5/9(°F−32) +273.15

Precision

How close a series of measurments are to each other.

Accuracy

How close a value is to the actual or accepted value. Ex. density of water is 1g experiments may yield diff value

Avogadro’s Number

6.022 × 10²³ particles

Ratio for Pure Water

1g = 1mL

Inches to centimeters converstion factor

1in = 2.54cm

kilograms to pounds conversion factor

1kg = 2.2lb

1ft = 0.0028

Giga

10⁹ (G)

Mega

10⁶ (M)

Kilo

10³ (k)

Hecto

10² (h)

Deka

10^1 (da)

Deci

10^-1 (d)

Centi

10^-2 (c)

Mili

10^-3 (m)

Micro

10^-6 (μ)

Nano

10^-9 (n)

Pico

10^-12 (p)

Ryberg Constant for Energy

△E = -2.18 × 10^-18 J

Transitional Energy Equation

△E = -2.18 × 10^-18 J(1/n² - 1/n²)

Planck’s Constant (h)

6.626 × 10^-34 m² kg / s

When to use E = hv

To Calculate the energy of single photon (particle of light)

When E = hc/λ

To Calculate the energy of single photon

OR find its wave length

Photon

Single particle of light

Homonuclear Diatomic Molecules

H₂, N_2, F_2, O_2, I_2, Cl_2, Br₂ (Have No Fear Of Ice Cold Beer)

Observation

A witnessed observation that can be recorded.

Interpretation

A possible explanation of the reason behind a phenomenon.

Natural Law

An observation that applies to many different systems. (Law of Conservation of Mass)

Law

A statement that defines how a particular phenemonon occurs.

Theory

Is an attempt to explain why a phenonmenon occurs.

Law of Definite Proportions

A given compound is always made of the exact same elements with the exact same weight ratio. Water is always 89% oxygen & 11% hydrogen by weight

Law of Multiple Proportions

if two elements can combine to form different compounds, they do so in simple, whole-number atomic recipes. (ratio between H2O & H2O2) is 2:1