First. moles is just a label for a number of things. just like a
dozen = 12, a gross = 144, a mole = 6022 with another 20 zeros after the
2
next
moles = mass / molecular weight.
molecular weight = sum of atomic mass from the periodic table
atomic mass MnO2 = atomic mass Mn + 2 x atomic mass O
= 54.94 + 2 x 16 = 86.94 g/mole
so moles MnO2 = 98.0 grams / (86.94 g/mole) = 1.13 moles
notice that I only gave 3 digits? that because of sig figs read the link below if you don't understand....
mw C5H12 = 5 x 12 + 12 x 1 = 72 g/mole
so moles C5H12 = 12.0 g / 72.0 g/mole = 0.167 moles
mw XeF6 = 131.3+ 6 x 19.00 = 245.3
so moles XeF6 = 100 g / 245.3 g/mole = 0.4077 moles
I've also provided a link to a periodic table. if you need atomic weights click on any element and it will give you the
details.
This problem has two parts; the first one asking for the concentration of NaBr given both its mass and volume and the second one asking for its volume given both mass and concentration. The answers turn out to be 0.158 M and 211 mL.
<h3>Molarity</h3>
In chemistry, the use of units of concentration depends on both the substances to analyze and their amounts. In such a way, for molarity, one needs the following relationship between the moles of solute and volume of solution:

Thus, for the first part of the problem we first calculate the moles in 2.60 g of NaBr via its molar mass:

Next, we convert the 160. mL to L by dividing by 1000 in order to obtain 0.160 L to subsequently calculate the molarity:

Next, since the moles remain the same and for the second part we are asked for the volume given the concentration, one can solve for the volume so as to obtain:

That in milliliters turns out to be:

Learn more about molarity: brainly.com/question/10053901
Answer:
The variables to be examined in relation to carbon dioxide use are the amount of light exposure and amount of dissolved CO2. Phenol red is yellow/orange under acidic conditions, that is when the pH of the solution is less than 7 (e.g. pH = 6). This occurs when the concentration of CO2 is high.
Explanation:
is this correct
Answer:
Explanation:
Drug for the treatment of disease. Chemistry contributes to the preparation and use of materials for surgery (sutures, artificial skin, and sterile materials). ...
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Blood glucose testing device.