Calculate the mass of CaCL2 formed when 5 moles of chlorine reacts with calcium metal

555 g of CaCl₂

Explanation:

We'll begin by writing the balanced equation for the reaction. This is given below:

Ca + Cl₂ —> CaCl₂

From the balanced equation above,

1 mole of Cl₂ reacted to produce 1 mole of CaCl₂.

Next, we shall determine the number of mole of CaCl₂ produced by the reaction of 5 moles of Cl₂. This can be obtained as follow:

From the balanced equation above,

1 mole of Cl₂ reacted to produce 1 mole CaCl₂.

Therefore, 5 moles of Cl₂ will also react to produce 5 moles of CaCl₂.

Thus, 5 moles of CaCl₂ were obtained from the reaction.

Finally, we shall determine the mass of 5 moles of CaCl₂. This can be obtained as follow:

Mole of CaCl₂ = 5 moles

Molar mass of CaCl₂ = 40 + (35.5×2)

= 40 + 71

= 111 g/mol

Mass of CaCl₂ =?

Mass = mole × molar mass

Mass of CaCl₂ = 5 × 111

Mass of CaCl₂ = 555 g

Therefore, 555 g of CaCl₂ were obtained from the reaction.

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.