NMAT - Chemistry

What is the chemical symbol for Potassium?

$$K$$

What is the chemical symbol for Sodium?

$$Na$$

What are Group 1 elements called?

Alkali metals (very reactive)

What is the common name for Group 18 elements?

Noble gases (very unreactive)

According to the lecture, what is the definition of electronegativity?

An atom's ability to attract electrons in a chemical bond.

Which element has the highest electronegativity value?

Fluorine ($F$)

In which directions does the atomic radius increase across the periodic table?

Increases down and left.

In which directions does electronegativity increase across the periodic table?

Increases up and right.

In which directions does ionization energy increase across the periodic table?

Increases up and right.

In which directions does metallic character increase across the periodic table?

Increases down and left.

What is the fundamental stoichiometry formula used to find Mass from Moles?

$$\text{Mass} = \text{Moles} \times \text{Molar Mass}$$

What are the approximate atomic masses for Hydrogen ($H$) and Carbon ($C$)?

$H = 1$, $C = 12$

What are the approximate atomic masses for Nitrogen ($N$) and Oxygen ($O$)?

$N = 14$, $O = 16$

What is the formula used to calculate percent composition?

$$\text{Percent composition} = \frac{\text{Mass of the element}}{\text{Total molar mass}} \times 100\%$$

How does a mixture differ from a compound in terms of proportions?

Mixtures have variable proportions, while compounds have fixed proportions.

How is a mixture typically separated compared to a compound?

Mixtures can be separated by physical methods; compounds can only be separated by chemical methods.

How can you usually identify an acid by its formula?

It usually begins with Hydrogen ($H$).

How can you usually identify a base by its formula?

It usually ends with Hydroxide ($OH$).

Which common exception is a base but does not contain an $OH$ group?

Ammonia ($NH_3$ )

Which common organic acid does not start with $H$ in its formula?

Acetic acid ($CH_3COOH$)

What is the scientific definition of temperature relative to particles?

A measure of the average kinetic energy of the particles in a sample.

What is the visual 'fingerprint' for identifying a carbohydrate structure?

Rings with many $OH$ (hydroxyl) groups.

What visual clues define the structure of a triterpene?

A long branched hydrocarbon chain with multiple double bonds and an absence of Oxygen or Nitrogen.

What is Ionization Energy

How hard it is to move an electron

How does Ionization Energy increase

Going up and right

How does metallic character increase in the periodic table?

Down & Left

How would you describe the top right corner of the periodic table?

High electronegativity and ionization energy

• hold electrons tightly

• are very electronegative

• require lots of energy to remove electrons

How would you describe the bottom left corner of the periodic table?

Large atomic radius and are very metallic; they easily lose electrons

What is the top number in elements?

Mass number (protons + neurons)

What is the bottom number in elements?

Atomic number (protons)

Alpha decay

Mass decreases by 4 and atomic number decreases by 2

Conjugate pairs

Differ by exactly 1 H+

β⁻ decay

Atomic number increases by 1

β+ decay

Atomic decreases by 1