B.
This method of expressing concentration is employed with solutions where both the solute and solvent are liquid. This is because it is easy to measure the volume of a liquid compared to that of a solid. Usually weight/weight is used in concentrations involving only solids.
Molar mass P2O5 = 31 x 2 + 16 x 5 => 142 g/mol
142 g ---------------- 6.02 x 10²³ molecules
0.920g g ------------ ( molecules )
molecules = 0.920 x ( 6.02 x 10²³ ) / 142
molecules = 5.53 x 10²³ / 142
= 3.89 x 10²¹ molecules
1 molecule P2O5 -------------------------- 7 atoms
3.89 x 10²¹ molecules -------------------- ( atoms )
atoms = ( 3.89 x 10²¹) x 7 / 1
atoms = 2.72 x 10²² atoms of P2O5
hope this helps!
Once you have constructed an effective hypothesis, the next step in the scientific inquiry process is to
test the hypothesis through experimentation. This is a great opportunity for students to start a science
notebook, if they have not yet started recording their progress.
Steps to Identifying and Conducting an Appropriate Experiment to Test a Hypothesis
1) Present Hypotheses
Make a list of all potential hypotheses to be tested.
2) Make Predictions
For each hypothesis, ask what would be true if the hypothesis were true.
3) Write the Experimental Procedure
The experimental procedure is a step-by-step recipe for the science experiment. A good
procedure contains enough detail that someone else could easily duplicate the
experiment. Once you have formed a hypothesis, you will need to develop your
experimental procedure to test whether your hypothesis is true or false.
4) Identify the Independent and Dependent Variables
The first step of designing the experimental procedure involves planning how to change
the independent variable and how to measure the impact that this change has on the
dependent variable. To guarantee a fair test when conducting the experiment, make sure
that the only thing changing is the independent variable. All controlled variables must
remain constant.
5) Design the Experiments
How can you identify an appropriate experiment that will effectively test your
hypothesis? Begin by asking yourselves, “What can I do that will give me one result if my
hypothesis is true, and a different result if my hypothesis is false?” Design at least one
possible experiment for each hypothesis. Be sure that each experiment tests only one
hypothesis.
The answer is D. obsidian. Or at least I think it is. Just guessing based off me playing Minecraft 6 years ago haha
