What is the correct order of processes in the accretion of planetesimals? Masses of matter form around dust grain, masses of matter collide, and atoms and molecules are added to dust grain.
Masses of matter collide, masses of matter form around dust grain, and atoms and molecules are added to dust grain.
Atoms and molecules are added to dust grain, masses of matter form around dust grain, and masses of matter collide.
Masses of matter collide, atoms and molecules are added to dust grain, and masses of matter form around dust grain.

Atoms and molecules are added to dust grain, masses of matter form around dust grain, and masses of matter collide.

Explanation:

Planetesimals are the foundation or fundamentals of planet formation. The mode of the formation is called accretion. In this process, dust grains or particles mixes with atoms and molecules to form a massive mass which later coalesce or collide to form planets.

The size of the planet formed is determined by the amount of masses of matter that collide.

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6