Question

the longer the reaction time is, the ✔️ lesser the reaction rate is. reaction time is ✔️ inversely proportional to reaction rate. complete the smaller the particle size, the the surface area. therefore, particle size is to surface area. done ✔️

Explanation:

For the first blank about particle size and surface area: As particle size decreases, the total surface area (since more particles are exposed) increases. So the word to fill is "greater". For the second blank, since as particle size gets smaller, surface area gets larger, they are inversely related? Wait, no—wait, smaller particle size means more surface area (e.g., a cube broken into smaller cubes has more total surface area). So particle size and surface area: when one decreases, the other increases, so they are inversely proportional? Wait, no, actually, particle size (diameter or volume per particle) and surface area per unit mass: as particle size decreases, surface area increases. So the relationship is that particle size is inversely proportional to surface area? Wait, no, let's think: if particle size (let's say radius \( r \)) of a spherical particle, surface area \( A = 4\pi r^2 \), volume \( V=\frac{4}{3}\pi r^3 \). For a given mass (so constant volume if density is constant), smaller \( r \) means more particles, so total surface area increases. So as particle size (individual particle's size) decreases, total surface area (for a given mass) increases. So the first blank: "greater" (the smaller the particle size, the greater the surface area). The second blank: "inversely proportional" (because when particle size decreases, surface area increases, so they are inversely related). Wait, but let's confirm: particle size and surface area (for a given amount of substance) – smaller particles have more surface area. So the relationship is that particle size is inversely proportional to surface area (or surface area is directly proportional to \( 1/\text{particle size} \)). So the first dropdown: "greater", second dropdown: "inversely proportional"? Wait, no, wait: if particle size is smaller, surface area is larger. So the first blank: "greater" (the smaller the particle size, the greater the surface area). Then, particle size and surface area: as particle size decreases, surface area increases, so they are inversely proportional. So the first blank: "greater", second blank: "inversely proportional". Wait, but let's check the first part: reaction time and reaction rate – longer reaction time means slower reaction rate (lesser rate), so inversely proportional. Then for particle size: smaller particle size means more surface area (greater surface area), so particle size and surface area: when particle size decreases, surface area increases, so they are inversely proportional. So the first blank: "greater", second blank: "inversely proportional".

Answer:

First blank: greater
Second blank: inversely proportional

(Note: The dropdown options likely include "greater" for the first blank and "inversely proportional" for the second blank, based on the relationship between particle size and surface area in chemical kinetics: smaller particle size increases surface area, and they are inversely proportional.)