What period is Zn (zinc) in?

Which of the solutions have greatest osmotic pressure 30% sucrose 60% sucrose or 30% magnesium sulfate?

timofeeve [1]

Answer:Osmotic pressure is the minimum amount of pressure a solution must exert in order to prevent from crossing a barrier by osmosis. Solute molecules have difficulty crossing semipermeable membranes, so the more solutes that are in a solution, the higher the osmotic pressure will be. Between 30% sucrose and 60% sucrose, 60% sucrose will have a greater osmotic pressure than 30% because it has a higher percentage of solutes. However, since sucrose has a higher potential to cross semipermeable membranes and is more absorbable than magnesium sulfate, magnesium sulfate would have a higher osmotic pressure than 60% sucrose even though 60% sucrose has higher molecules.

Explanation:

8 0

3 years ago

Need to find moles and molarity

valentinak56 [21]

You multiply the molarity by the volume in litres.
Explanation:
Molarity is the number of moles of a substance in one litre of solution. The official symbol for molarity is “c” (concentration), but many people use the old symbol “M”.
M
=
n
V
, where
n
is the number of moles and
V
is the volume in litres.
We can rearrange this equation to get the number of moles:
n
=
M
×
V

Example
:
How many moles of
NaCl
are contained in 0.300 L of 0.400 mol/L
NaCl
solution?
Solution:
n
=
0.300
L soln
×
0.400 mol NaCl
1
L soln
=
0.120 mol NaCl

4 0

4 years ago

A crystallographer measures the horizontal spacing between molecules in a crystal. The spacing is 15.93nm. What is the total wid

salantis [7]

0.00167265 mm

Explanation:

Given the spacing between the molecules in the crystal is 15.93 nm.

1 nm = $10^{-9}$ m

so 15.93 nm = 15.93 * $10^{-9}$ = 1.593 * $10^{-8}$ m

Spacing between 2 molecules is 1.593 * $10^{-8}$ m

So total width of 105 molecules crystal is 1.593 * $10^{-8}$ *105 = 167.265 * $10^{-8}$ m

We know that

1 m = 1000 = $10^{3}$ mm

So total width of 105 molecules crystal in millimeters is 167.265 * $10^{-8}$ * $10^{3}$

= 167.265 * $10^{-5}$ = 1.67265 * $10^{-3}$ mm = 0.00167265 mm

8 0

4 years ago

The student observed a decrease in temperature when the substances were combined. A milky substance was produced and fell to the

labwork [276]

Answer: Calcium Chloride & Baking Soda

Explanation:

I've done this before, combine Calcium Chloride & Baking Soda and it produces a milky substance.

3 0

3 years ago

The smell of dirty gym socks is caused by the compound caproic acid(contains H, C, O). Combustion of 0.844 g of caproic acid pro

adoni [48]

Answer: The molecular formula for the given organic compound is $C_2H_{32}O_4$

Explanation:

The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:

$C_xH_yO_z+O_2\rightarrow CO_2+H_2O$

where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.

We are given:

Mass of $CO_2=0.784g$

Mass of $H_2O=1.92g$

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

For calculating the mass of carbon:

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 0.784 g of carbon dioxide, $\frac{12}{44}\times 0.784=0.214g$ of carbon will be contained.

For calculating the mass of hydrogen:

In 18 g of water, 2 g of hydrogen is contained.

So, in 1.92 g of water, $\frac{2}{18}\times 1.92=0.213g$ of hydrogen will be contained.

Mass of oxygen in the compound = (0.844) - (0.214 + 0.213) = 0.417 g

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{0.214g}{12g/mole}=0.0134moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{0.213g}{1g/mole}=0.213moles$

Moles of Oxygen = $\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{0.417g}{16g/mole}=0.0261moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.0134 moles.

For Carbon = $\frac{0.0134}{0.0134}=1$

For Hydrogen = $\frac{0.213}{0.0134}=15.89\approx 16$

For Oxygen = $\frac{0.0261}{0.0134}=1.95\approx 2$

Step 3: Taking the mole ratio as their subscripts.

The ratio of C : H : O = 1 : 16 : 2

The empirical formula for the given compound is $CH_{16}O_2$

For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.

The equation used to calculate the valency is:

$n=\frac{\text{Molecular mass}}{\text{Empirical mass}}$

We are given:

Mass of molecular formula = 116.2 g/mol

Mass of empirical formula = 60 g/mol

Putting values in above equation, we get:

$n=\frac{116.2g/mol}{60g/mol}=1.94\approx 2$

Multiplying this valency by the subscript of every element of empirical formula, we get:

$C_{(1\times 2)}H_{(16\times 2)}O_{(2\times 2)}=C_2H_{32}O_4$

Hence, the molecular formula for the given organic compound is $C_2H_{32}O_4$

5 0

3 years ago