How do I find the hypothesis and null hypothesis of an article?

Let's start with the null hypothesis. A null hypothesis is a hypothesis that states there is no relationship between/among whatever is being tested. Generally speaking, the goal is to have a null hypothesis not supported. If it isn't supported, then researchers know that there is a relationship that exists. The null hypothesis might be difficult to find because not all researchers use a null hypothesis. If it is used, it will be located where a standard hypothesis is used. A standard research report/article will be divided into sections. One of the first sections is the introduction. The introduction will give a general overview of why the research was conducted in the first place. Often, the "research question(s)" is listed here, and it is often clearly labeled or announced to a reader. It can even begin "The purpose of the study . . . ."
Once you see the research question or purpose statement, you can have a fairly high degree of confidence that the hypothesis is going to follow shortly. Depending on the author, the hypothesis might begin something like the following: "We believe that such and such will happen." It's also possible that the researcher clearly tags the hypothesis by using that word. For example, "It was hypothesized that a . . . ."
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