In choosing a primary standard we generally
choose something that
1. All of these are properties we want in a
primary standard.
2. has a low percent purity.
3. None of these are properties we want in a
primary standard.
4. has several different possible reaction
pathways.
5. is insoluble.
6. has a low molecular weight.
The answer is 3, none of these describe a primary standard
Perhaps you need to rephrase this question. As written it makes no sense to me.
you are supposed to chose the answer (1-6) that best finishes the beginning sentence
In choosing a primary standard, we generally want a substance that possesses certain properties. Let's carefully analyze each option to determine which ones are desirable for a primary standard:
1. "All of these are properties we want in a primary standard." This statement suggests that all the options listed are desirable properties for a primary standard. However, it is important to verify the accuracy of this statement by assessing each option individually.
2. "Has a low percent purity." A primary standard should ideally have a high degree of purity to ensure accurate and precise measurements. A low percent purity would introduce impurities that could affect the reliability of the standard, so this option is not desirable for a primary standard.
3. "None of these are properties we want in a primary standard." This statement contradicts the initial question, which states that we generally choose something with certain properties as a primary standard. Therefore, this option can be eliminated.
4. "Has several different possible reaction pathways." A primary standard should have a well-defined chemical structure and exhibit a specific, predictable reaction pathway. Having multiple possible reaction pathways could lead to ambiguity and the potential for inaccurate results. So, this option is also not desirable for a primary standard.
5. "Is insoluble." Insolubility can present challenges when trying to prepare accurate solutions of known concentration. A primary standard should be readily soluble to facilitate the preparation of consistent and reliable solutions. Hence, this option is not desirable.
6. "Has a low molecular weight." While the molecular weight of a primary standard may vary depending on the specific analytical method, generally, a higher molecular weight is preferred. This is because a higher molecular weight often implies greater accuracy in weighing due to reduced errors associated with weighing small quantities. Therefore, a low molecular weight is not typically desirable for a primary standard.
Based on the analysis of each option, it can be concluded that option 1, "All of these are properties we want in a primary standard," is unlikely to be correct. The most desirable properties for a primary standard are high purity, a well-defined chemical structure, and solubility.