List down 3 Filipino world-class instrumentalists. 1. 2. 3.

2. Zn + HCI. ZnCl2 + H2 what reaction is this

steposvetlana [31]

Answer: Type of Chemical Reaction: For this reaction we have a combination reaction. Balancing Strategies: When we add zinc to hydrochloric acid we end up with zinc chloride, a salt, and hydrogen gas. This reaction is actually a good way to make hydrogen gas in the lab.

5 0

3 years ago

A certain liquid has a normal boiling point of and a boiling point elevation constant . A solution is prepared by dissolving som

jek_recluse [69]

The question is incomplete, the complete question is:

A certain substance X has a normal freezing point of $-6.4^oC$ and a molal freezing point depression constant $K_f=3.96^oC.kg/mol$ . A solution is prepared by dissolving some glycine in 950. g of X. This solution freezes at $-13.6^oC$ . Calculate the mass of urea that was dissolved. Round your answer to 2 significant digits.

Answer: The mass of glycine that can be dissolved is $1.3\times 10^2g$

Explanation:

Depression in the freezing point is defined as the difference between the freezing point of the pure solvent and the freezing point of the solution.

The expression for the calculation of depression in freezing point is:

$\text{Freezing point of pure solvent}-\text{freezing point of solution}=i\times K_f\times m$

OR

$\text{Freezing point of pure solvent}=\text{Freezing point of solution}=i\times K_f\times \frac{m_{solute}\times 1000}{M_{solute}\times w_{solvent}\text{(in g)}}$ ......(1)

where,

Freezing point of pure solvent = $-6.4^oC$

Freezing point of solution = $-13.6^oC$

i = Vant Hoff factor = 1 (for non-electrolytes)

$K_f$ = freezing point depression constant = $3.96^oC/m$

$m_{solute}$ = Given mass of solute (glycine) = ?

$M_{solute}$ = Molar mass of solute (glycine) = 75.07 g/mol

$w_{solvent}$ = Mass of solvent = 950. g

Putting values in equation 1, we get:

$-6.4-(-13.6)=1\times 3.96\times \frac{m_{solute}\times 1000}{75.07\times 950}\\\\m_{solute}=\frac{7.2\times 75.07\times 950}{1\times 3.96\times 1000}\\\\m_{solute}=129.66g=1.3\times 10^2g$

Hence, the mass of glycine that can be dissolved is $1.3\times 10^2g$

5 0

3 years ago

How many electrons are found in their outer shell ?

dezoksy [38]

The answer is eight electrons.

3 0

3 years ago

A graduated cylinder is filled with 60.0 ml of water. A cube, made of aluminum, is carefully dropped into the cylinder. Aluminum

katen-ka-za [31]

Answer:

65 ml

Explanation:

The aluminum will not float , so it will displace a volume of fluid equal to its volume.

13.5 gm / 2.7 gm/ml = 5 ml

the new graduated cylinder measurement will be 60 + 5 = 65 ml

3 0

2 years ago

People tend to speak more quietly in restaurants than they do when they are having an ordinary conversation Restaurant conversat

MArishka [77]

Answer:

A loud ordinary conversation following the supplied information in the question is about 4500 dB. But, in the official decibel system measure a loud conversation does not overcome 100 dB.

Explanation:

Using the supplied data of the exercise, we say that in a restaurant conversation the value is 45 dB. If we multiply this by 100 we will have a value for a laud ordinary conversation.

45×100 = 4500 dB.

but as I mentioned in the answer, in the official decibel system measure a loud conversation between 2 man reaches a maximal of 100 dB.

6 0

4 years ago

List down 3 Filipino world-class instrumentalists.1.2.3.​

List down 3 Filipino world-class instrumentalists.1.2.3.