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What effect would the incomplete drying of a sample (for example, the incomplete removal of a re-crystallization solvent) on per

Varvara68 [4.7K]

Answer:

It will lead to overestimation of the percent recovery

Explanation:

The percent recovery refers to the percentage of the pure compound recovered after a chemical process. It is a ratio of the pure compound recovered to the original substance multiplied by 100%.

If the sample was incompletely dried and the recrystallization solvent is still present, the percent recovery will be overestimated and we will have a value that is greater than the accurate percent recovery due to solvent impurities present.

5 0

2 years ago

a rectangular piece of aluminum foil measures 13.72 cm x 8.63 cm and has a mass of 3.1 g. Find how thick it is

Leona [35]

The two dimensions of aluminum foil are given 13.72 cm and 8.63 cm respectively with mass 3.1 g.

The density of aluminum is $2.7 g/cm^{3}$ . It is defined as mass per unit volume thus, volume of aluminum can be calculated as follows:

$V=\frac{m}{d}$

Putting the values.

$V=\frac{3.1 g}{2.7 g/cm^{3}}=1.148 cm^{3}$

The volume of cuboid is $l\times b\times h$ , the length and breadth are given, height can be calculated as follows;

$h=\frac{V}{l\times b}$

Putting the values,

$h=\frac{1.148 cm^{3}}{(13.72 cm)(8.63 cm)}=0.009695 cm$

Or, approximately 9.7\times 10^{-3}cm

Therefore, thickness of aluminum foil is $9.7\times 10^{-3}cm$

7 0

3 years ago

What information does an empirical formula give?

r-ruslan [8.4K]

Answer:

C. The lowest whole-number ratio of atoms in a molecule.

Explanation:

Hello there!

In this case, according to the definition of the empirical and the molecular equations, it is possible for us to consider the following example of molecular formula, C4H10, whose empirical formula is C2H5.

In such a way, it is possible for us to say that the empirical formula gives C. The lowest whole-number ratio of atoms in a molecule, as it is the result of the simplification of the molecular formula when possible.

Regards!

3 0

3 years ago

What is used to determine the number of each atom in an ionic formula?

Nutka1998 [239]

the oxidation state of each atom

3 0

2 years ago

One mole of oxygen gas is at a pressure of 6.00 atm and a temperature of 27.0°C. (a) If the gas is heated at constant volume unt

Umnica [9.8K]

Answer: a) 900 K

b) 1200 K

Explanation:

According to the ideal gas equation:

$PV=nRT$

P = Pressure of the gas = 6.00 atm

V= Volume of the gas = ?

T= Temperature of the gas = 27°C = 300 K $0^00C=273K$

R= Gas constant = 0.0821 atmL/K mol

n= moles of gas = 1

$V=\frac{nRT}{P}=\frac{1\times 0.0821\times 300}{6.00}=4.10L$

a) To calculate the final temperature of the system, we use the equation given by Gay-Lussac Law. This law states that pressure of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

$\frac{P_1}{T_1}=\frac{P_2}{T_2}$