5 Select the correct answer.
A chemistry student heated Iron (a graylsh solid) with sulfur (a yellow solid) and observed a black, lumpy solid forming. What is the student's
conclusion?
A. A physical change has occurred, and a new substance has formed.
B. A chemical change has occurred, and a new substance has formed.
OC A physical change has occurred, and the reactants and products have the same properties.
D. A chemical change has occurred, and the reactants and products have the same properties.
Reset
Next
O 2020 Edmentum. All rights reserve

The scheme below is from a series of reactions that are part of a synthesis of vitamin a. answer the following questions with reference to this scheme. (i) what is "reagent a"? (ii) draw a step-by-step mechanism which explains the formation of compound c from compound b (iii) which reagents would you use to form compound e from compounds c and d (reagents b and c)? for each reagent suggested above in (ii) explain the role of the reagent in the reaction to (iv) form compound e. you may wish to do this by drawing a mechanism. 1. addition of reagent a но reagent a 2. н, о" thо oh нон-с compound a. compound b. compound c .ch-оh 1. reagent b "сно 2. reagent c сh oh compound e. compound d.

Marcel just purchased 1.69 grams of iron fillings in order to make living putty for his 6 year old niece. how many moles of iron are made in his sample?

What is the percent composition of ca(oh)2? 37.7% ca, 53.0% o, and 10.3% h 45.5% ca, 38.2% o, and 16.3% h 54.0% ca, 43.0% o, and 2.7% h 64.7% ca, 27.0% o, and 8.3% h