Atomic Structure and Trends in Chemistry Explained

This video tutorial explains how to score the Unit 1 FRQ assignment, focusing on atomic structure, ionic compounds, and mass spectrometry. It covers the scoring criteria, including the importance of showing work and providing explanations. The tutorial discusses atomic radius and ionization energy trends, identifying elements forming brittle ionic compounds, and analyzing isotopes using mass spectrometry. It also provides guidance on calculating average atomic mass and writing electron configurations.

What is the point value for each answer in the Unit 1 FRQ assignment?

• Four points

• One point

• Two points

• Three points

Why is the atomic radius of potassium larger than that of sodium?

• Potassium has a greater shielding effect.

• Sodium has more protons.

• Potassium has fewer energy levels.

• Sodium has a higher energy level.

What trend is observed in ionization energy across a period from left to right?

• It remains constant.

• It fluctuates randomly.

• It decreases.

• It increases.

Which element is likely to form a brittle ionic compound with the formula M2O?

• Helium

• Carbon

• Lithium

• Boron

How can a chemist determine the compound in a sample of known mass containing either K2O or K2O2?

• By checking the compound's solubility.

• By observing the compound's brittleness.

• By calculating the percentage of potassium.

• By measuring the color of the compound.

How many isotopes of an element were identified in the mass spectrometry data?

• Four

• Two

• One

• Three

What is the first step in calculating the average atomic mass using mass spectrometry data?

• Subtract the smallest mass from the largest mass.

• Multiply the relative abundance by the mass of each isotope.

• Add the masses of all isotopes.

• Divide the total mass by the number of isotopes.

Which element was identified from the mass spectrometry data with a peak at 24?

• Magnesium

• Calcium

• Potassium

• Sodium

What is the ground state electron configuration for magnesium?

• [Ne] 3s1

• [Ne] 3s2

• [Ar] 4s2

• [He] 2s2 2p6

If a student identifies the wrong element but writes the correct electron configuration for it, what happens?

• They gain points for the configuration.

• They gain points for the element.

• They gain no points.

• They lose all points.