I agree with what you've chosen for question two and three.
I would choose C for the fourth question and argue that you shall also go with C for question five.
One of the main ideas about repetition is to have multiple <em>Trials</em>- or independent experiments-<em> </em>for a single independent variable using identical experimental setup. The table presented in option C is the only one among the four choices that allots spaces for measurements from multiple independent experiments.
Hypotheses are predictions of the outcome of a particular experiment. A hypothesis is <em>correct</em> only if it accurately describes the outcome of an experiment. The <em>hypothesis</em>, not the data, would have to be revised if the two doesn't fit. The researcher could keep developing and testing new hypotheses until arriving at a correct one.
Additionally, I would prefer option B over option D in the first question- responses to that question can depends on what your teacher says about the validity of different sources, given that <em>neither </em><em>B</em><em> nor </em><em>D</em><em> </em> are reliable as sources that one would like to cite in a paper.
The rate of a reaction can be increased by:
-using a catalyst- it lowers the activation energy and leads to less energy required to break bonds of reactants. This lower activation energy leads to more products formed with less time, hence an increase reaction rate.
-increasing temperature- the particles of a molecule move faster and undergo more collision which leads to an increase in the speed of the reaction.
-increasing pressure- means there is more particles of reactants in a reduced volume. The particles do not need to move long distances to find another particle to react with, hence the rate of reaction increases.
Using an inhibitor will not increase the rate of the reaction because, an inhibitor binds to the active site where a catalyst is supposed to act. This means a higher activation energy and thus a decrease in reaction rate.
Likewise, decreasing the concentration implies few particles available to collide with each other and that slow down the speed of the reaction.
It's a hazard symbol for irritant.
Answer:
Percent error = 12.5%
Explanation:
In a measurement you can find percent error following the formula:
Percent error = |Measured value - Accepted Value| / Acepted value * 100
Based on the data of the problem, accepted value is 22.4L and the measured Value (Value of Sara) was 19.6L.
Replacing:
Percent error = |Measured value - Accepted Value| / Acepted value * 100
Percent error = |19.6L - 22.4L| / 22.4L * 100
Percent error = |-2.8L| / 22.4L * 100
Percent error = 2.8L / 22.4L * 100
Percent error = 12.5%