Ms. block's students are studying chemical reactions as well as the law of conservation of matter. a classic reaction occurs when a metal is added to hydrochloric acid. miguel and kai are about to add 30g of hydrochloric acid (hcl) to 30g of magnesium (mg) in a large test tube. how could you adapt the boys experimental design so they would definitely be testing the law of conservation of matter? a) the boys could use less hydrochloric acid to produce less gas bubbles. b) the boys should use a container, such as a flask, that is larger than a test tube. c) the boys could cover the end of the test tube with a balloon to capture the escaping gas. d) one of the boys could place a hand over the end of the test tube to create a closed system.

Follow the steps provided in the simulation to add water to the graduated cylinder, select one of the three samples (copper, silver, or gold), set its mass to the values given in the statements below, and calculate its density. here is a summary of the steps required: add water by clicking and holding prepare a known volume of water button. until the desired volume of water has been added. if more than the desired volume is added, click the reset button. button and redo the procedure. a single click will add about 21.0 ml of water. to set the mass, click and hold weigh out metal button. until the desired amount of metal is added to the weighing pan. once the desired mass of the metal is added, release the button. transfer the metal to water and then click on calculate density button. to see how the density is calculated using water displacement to measure the volume of the solid. to save time you can approximate the initial volume of water to â±1 ml and the initial mass of the solid to â±1 g. for example, if you are asked to add 23 ml of water, add between 22 ml and 24 ml. which metals in each of the following sets will have equal density? check all that apply.

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.

Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. in the first step, nitrogen and hydrogen react to form ammonia: (g) (g) (g) in the second step, ammonia and oxygen react to form nitric acid and water: (g) (g) (g) (g) calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions. round your answer to the nearest .