The balanced chemical equation, c (s) + o2 (g) co2 (g), can be expressed in words
1. solid carbon plus oxygen gas yields cobalt dioxide
2.carbon plus diatomic oxygen yields cobalt dioxide
3. solid carbon plus oxygen gas yields carbon dioxide gas
4. solid calcium plus oxygen gas yields calcium dioxide gas

The correct answer is Option 3.

Explanation:

When solid carbon burns in the presence of oxygen gas, it leads to the production of a gas known as carbon dioxide.

To write a chemical equation, we must follow some of the rules:

The reactants are always written on the left side of the direction arrow.A '+' sign is added between the reactants, if more than one reactants are present.An arrow is added after all the reactants are written. The arrow indicates the direction of reaction.The products are always written on the right side of the direction arrow.A '+' sign is added between the products, if more than one products are present.

Here, carbon and oxygen are the reactants and carbon dioxide is the product.

The chemical equation representing this reaction follows:

Here, (s) represents that the carbon is in solid state and (g) represents that the oxygen and carbon dioxide are in gaseous state.

Hence, the correct answer is Option 3.

Answer: abeexplanation:

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.

Hairy thick gross thing? idk