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2 years ago

Please help ill give you points and brainliest please

Chemistry

1 answer:

Paul [167]2 years ago

3 0

Answer:

Answers with detail are given below

Explanation:

1) Given data:

Mass of Rb₃Rn = 76.19 g

Number of moles = ?

Solution:

Number of moles = mass/molar mass

Molar mass = 478.43 g/mol

Number of moles = 76.19 g/ 478.43 g/mol

Number of moles = 0.16 mol

2) Given data:

Mass of FrBi₂ = 120.02 g

Number of moles = ?

Solution:

Number of moles = mass/molar mass

Molar mass = 640.96 g/mol

Number of moles = 120.02 g/640.96 g/mol

Number of moles = 0.19 mol

3) Given data:

Mass of Zn₂F₃ = 88.24 g

Number of moles = ?

Solution:

Number of moles = mass/molar mass

Molar mass = 187.73 g/mol

Number of moles = 88.24 g/ 187.73 g/mol

Number of moles = 0.47 mol

4) Given data:

Number of moles of Sb₄Cl = 1.20 mol

Mass of Sb₄Cl = ?

Solution:

Number of moles = mass/molar mass

Molar mass = 522.49 g/mol

Mass = Number of moles × molar mass

Mass = 1.20 mol × 522.49 g/mol

Mass = 626.99 g

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2. A cylinder of compressed gas has a volume of 350 cm3 and a pressure of

slamgirl [31]

Answer: 3173.9cm3

Explanation:Please see attachment for explanation

7 0

2 years ago

Match the scientist with their scientific idea. Question 2 options: Substances combine or break apart to create new, different s

aev [14]

Answer:

1. Democritus - Matter was made of different kinds of things.

2. Bernoulli- Gases are formed from tiny particles so small you can’t see them. The particles are spread out into a certain area and move when people walk through them.

3. Priestley- Substances combine or break apart to create new, different substances.

Explanation:

1. Democritus was a philosopher who because of his immense contribution to atomic theory was regarded as the "FATHER OF SCIENCE". His idea was that matter was made of different kinds of things called which he called ATOMOS meaning ATOM.

2. Daniel Bernoulli was another outstanding mathematician and scientist who played a major part in the kinetic molecular theory of gases via his "HYDRODYNAMICA". His idea, which states that "gases are formed from tiny particles so small you can’t see them. The particles are spread out into a certain area and move when people walk through them"

was based on fluid dynamics.

3. Joseph Priestley is remarkably known for his 1774 discovery of oxygen. His findings that air is a mixture of gases and not just a substance made of one element paved the way for his idea that " Substances combine or break apart to create new, different substances".

4 0

3 years ago

Calculate the change in pH when 71.0 mL of a 0.760 M solution of NaOH is added to 1.00 L of a solution that is 1.0O M in sodium

Eddi Din [679]

Explanation:

It is known that $pK_{a}$ value of acetic acid is 4.74. And, relation between pH and $pK_{a}$ is as follows.

pH = pK_{a} + log $\frac{[CH_{3}COOH]}{[CH_{3}COONa]}$

= 4.74 + log $\frac{1.00}{1.00}$

So, number of moles of NaOH = Volume × Molarity

= 71.0 ml × 0.760 M

= 0.05396 mol

Also, moles of $CH_{3}COOH$ = moles of $CH_{3}COONa$

= Molarity × Volume

= 1.00 M × 1.00 L

= 1.00 mol

Hence, addition of sodium acetate in NaOH will lead to the formation of acetic acid as follows.

$CH_{3}COONa + NaOH \rightarrow CH_{3}COOH$

Initial : 1.00 mol 1.00 mol

NaoH addition: 0.05396 mol

Equilibrium : (1 - 0.05396 mol) 0 (1.00 + 0.05396 mol)

= 0.94604 mol = 1.05396 mol

As, pH = pK_{a} + log $\frac{[CH_{3}COONa]}{[CH_{3}COOH]}$

= 4.74 + log $\frac{0.94604}{1.05396}$

= 4.69

Therefore, change in pH will be calculated as follows.

pH = 4.74 - 4.69

= 0.05

Thus, we can conclude that change in pH of the given solution is 0.05.

8 0

2 years ago

1-Bromopropane is treated with each of the following reagents. Draw the major substitution product if the reaction proceeds in g

sammy [17]

Answer:

Explanation:

If we look at the structure of 1-Bromopropane; we will see that it is a derivative of alkane family by the the substitution of an alkyl group. The position of the Bromine in the propane is 1, making 1-Bromopropane a primary alkyl-halide.

Primary alkyl - halide undergo SN2 mechanism. This nucleophilic reaction needs to be a strong alkyl halide , such as 1-Bromopropane used otherwise it will result to a reactive mechanism if a weak electrophile is used.

However, the critical and the main objective here is to Draw the major substitution product if the reaction proceeds in good yield. If no reaction is expected or yields will be poor, draw the starting material in the box. If a charged product is formed, be sure to draw the counterion.

The attached diagrams portraying this notions is shown in the attached file below.

5 0

2 years ago

Anthracite coal d) is the most abundant grade of coal e) is very soft and burns at high temperatures a) causes the most air poll

forsale [732]

Answer: The correct option is C ( is very hard and burns cleanly).

Explanation:

COAL is a form of rock that is made up of mostly carbon amongst other elements which includes sulphur, nitrogen, hydrogen and oxygen. There are different types of coal which include:

--> anthracite ( 90% carbon)

--> bituminous coal ( 70-90% carbon)

--> lignite ( 60- 70% carbon) and

--> peat (60 % carbon).

Anthracite is the type of coal that contains the highest carbon content ( 90% carbon). This makes it very hard and is often a times referred to as HARD COAL. Anthracite is a higher quality coal for domestic and open fire heating. This is because it contains less impurities than other type of coal and thereby making it to BURN CLEANLY avoiding atmospheric pollution.

6 0

2 years ago

Please help ill give you points and brainliest please ​

Please help ill give you points and brainliest please