Which of the following is an example of how a scientist might use a model

a. marbles placed inside a hollow sphere are used to describe protons in a nucleus

b. stopwatches measure the amount of time it takes for runners to complete a mile

c. microscopes are used to magnify a group of cells on sets of slides

d. a wrench is used to tighten a nut onto a piece of wood

Which statement best describes the flow of energy in this scenario

The rate constant for the reaction below is 6.2 x 10−5 mol l−1 s −1. if the initial concentration of a is 0.0500 m, what is its concentration after 115 s?

Plzz a sample of table sugar (sucrose, c12h22o11) has a mass of 7.801 g. ● a) calculate the number of moles of c12h22o11 in the sample b) calculate the number of moles of each element in c12h22o11 (number of moles of c, number of moles of h & number of moles of o) in the sample. (use your answer from part a as your starting point.) show your work and highlight your final answer. calculate the number of atoms of each element in c12h22o11 (number of atoms of c, number of atoms of h & number of atoms of o) in the sample. (use your answers from part b as your starting for each element.) show your work and highlight your final answer.