The viscosity of water is the thickness of water (it might also be considered the stickiness when talking about other fluids). Water has many properties, and the viscosity of water influences in many of them. We can take the surface tension of a liquid as an example. The more viscous a substance is, higher will the surface tension be and vice versa since there will be a higher and lower attraction between molecules respectively.
→ The surface tension of water is something really important since it contributes in many ways to the environment and if you think about it, if the water was a little less viscous, there wouldn't be water since the viscosity of water makes it resistant to evaporation to a certain degree.
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BioTeacher101
Answer:
Empirical: OH
Molecular: 
Explanation:
First of all, we are going to use the formula: mass = no. moles x Molar Mass And rearrange it to find No. moles: No. moles = mass/Molar Mass
Let's start with Hydrogen:
The given mass is 0.44g, and hydrogen's molar mass is 1.01, therefore the number of moles is: 0.44/1.01 = 0.4356
Now we do the same for Oxygen:
Given mass = 6.92, Molar mass of Oxygen = 16.00, No. Moles = 6.92/16.00 = 0.4325
Now we identify the smaller one (Oxygen as 0.4325 < 0.4356) and we divide both values by that number:
0.4325/0.4325 = 1
0.4356/0.4325 = 1.01
We round both to the nearest 0.2 or 0.25 (depending on what you're taught), and we get: 1 and 1.
This means that the empirical formula has one of each: OH
Now to find the molecular formula we find the relative mass of OH and divide the given mass by that:
M(OH) = 16.00+1.01 = 17.01
34.00/17.01 = 2
We now multiply both by this number to get:

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The exchange of oxygen, food, and waste between mother and fetus occur in the placenta.