"Theory relates to a model in science because it presents the possible paradigms and patterns of the said concept and fact. It explains and elaborates the phenomenon of why it happened, how it happened and the factors that are invovlved in the process. A theory is a possible explanation of certain occurence.
in addition, any time a scientific theory is challenged, it means it's not a good theory. And this statement is not valid. In theoretical models, they are revisited when there are further studies and discoveries found in a certain area where they can be remodeled and reintegrated instead of disregarding its credibility. Models, theories and paradigms are not challenged but rather encouraged, they are supported in many studies since these theories and models were created in order for us to understand a certain phenomenon but it would likely help the scientific society to be updated in the new forms or spheres of improvement rather than discouragement."
1,2,3, or 4. Generally, carbon likes to make 4 bonds to 4 different atoms. For example, in methane(CH4), Carbon makes 4 bonds to 4 hydrogens. However, Carbon can also make double and triple bonds to atoms. This means that of the 4 bonds, more are used to bond to one thing. For example, in the compound CN, Carbon bonds to hydrogen on one side and triple bonds to Nitrogen on the other. This shows carbon can bond to at 2 atoms as well as 4 at a time. using a one double bond carbon would only bond to 3 atoms. I cant think of an example where carbon only bonds to one other atom without breaking the octet rule, but all the other values can be validated through examples. So, I still think the bottom answer is correct. Hope this helped!
To start one difference between the two is that a scientific experiment is meant to be repeated and to be formed into a theory and/or a scientific law. Scientific experiments also use different types of data, for instance, you could be recording how much a plant grows in a month, in an experiment you would focus on the types of soil being used. In an investigation you would observe how tall the plant actually grew.
I can tell you there certainly is enough information, so we can eliminate the fourth option right away.
Group two elements tend to form 2+ cations, and nitrogen forms 3- anions. To make a stable substance, we need those to cancel out. Calling the group 2 element X:
N2X3 would cause the charge to be 2(-3) + 3(2) = 0
This would mean 3 ions of X and 2 anions of N would be a stable ionic compound.
