1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
s2008m [1.1K]
3 years ago
10

Which of the following elements is a representative element?

Chemistry
1 answer:
Lubov Fominskaja [6]3 years ago
5 0
B. aluminum is the representative element. :)
You might be interested in
Which statement applies to electronegativity?
densk [106]

<u>Answer:</u> The correct answer is Option A.

<u>Explanation:</u>

Electronegativity is defined as the tendency of an atom to attract the shared pair of electrons towards itself whenever a bond is formed.

This property increases as we move from left to right across a period because the number of charge on the nucleus gets increased and electrons are attracted more towards the nucleus.

This property decreases as we move from top to bottom in a group because the electrons get add up in the new shells which make them further away from the nucleus.

Thus, the correct answer is Option A.

7 0
3 years ago
Calculate the work done when an ideal gas expands isothermally and reversibly in a piston and cylinder assembly for expansion of
pantera1 [17]

Answer:

W=5743.1077\ J

Explanation:

The expression for the work done is:

W=RT \ln \left( \dfrac{P_1}{P_2} \right)

Where,

W is the amount of work done by the gas

R is Gas constant having value = 8.314 J / K mol

T is the temperature

P₁ is the initial pressure

P₂ is the final pressure

Given that:

T = 300 K

P₁ = 10 bar

P₂ = 1 bar

Applying in the equation as:

W=8.314\times 300 \ln \left( \dfrac{10}{1} \right)

W=300\times \:8.314\ln \left(10\right)

W=2.30258\times \:2494.2

W=5743.1077\ J

5 0
3 years ago
Which factor can increase the potential energy of an object?
OLEGan [10]

Answer:

Increase in height from the ground.

Explanation:

Potential energy =mass×acceleration due to gravity×height.

P.E= mgh

4 0
3 years ago
What is the pH of a solution made by mixing 30.00 mL 0.10 M HCl with 40.00 mL of 0.10 M KOH? Assume that the volumes of the solu
nirvana33 [79]

Answer:

pH = 12.15

Explanation:

To determine the pH of the HCl and KOH mixture, we need to know that the reaction is  a neutralization type.

HCl  +  KOH  →  H₂O  +  KCl

We need to determine the moles of each compound

M = mmol / V (mL) → 30 mL . 0.10 M = 3 mmoles of HCl

M = mmol / V (mL) → 40 mL . 0.10 M = 4 mmoles of KOH

The base is in excess, so the HCl will completely react and we would produce the same mmoles of KCl

HCl  +  KOH  →  H₂O  +  KCl

3 m       4 m                       -

             1 m                      3 m

As the KCl is a neutral salt, it does not have any effect on the pH, so the pH will be affected, by the strong base.

1 mmol of KOH has 1 mmol of OH⁻, so the [OH⁻] will be 1 mmol / Tot volume

[OH⁻] 1 mmol / 70 mL = 0.014285 M

- log [OH⁻] = 1.85 → pH = 14 - pOH → 14 - 1.85 = 12.15

3 0
3 years ago
What is the theoretical yield of methanol (CH3OH) when 12.0 grams of H2 is mixed with 74.5 grams of CO? CO + 2H2 CH3OH
AlladinOne [14]
1) We need to convert 12.0 g of H2 into moles of H2, and <span> 74.5 grams of CO into moles of CO
</span><span>Molar mass of H2:    M(H2) = 2*1.0= 2.0 g/mol
Molar mass of CO:   M(CO) = 12.0 +16.0 = 28.0 g/mol

</span>12.0 g  H2 * 1 mol/2.0 g = 6.0 mol H2
74.5 g CO * 1 mol/28.0 g = 2.66 mol CO

<span>2) Now we can use reaction to find out what substance will react completely, and what will be leftover. 

                                  CO       +         2H2   ------->      CH3OH  
                                 1 mol              2 mol
given                        2.66 mol          6 mol (excess)

How much
we need  CO?           3 mol              6 mol

We see that H2 will be leftover, because for 6 moles H2  we need 3 moles CO, but we have only 2.66 mol  CO.
So, CO will react completely, and we are going to use CO to find  the mass of CH3OH.

3)                              </span>CO       +         2H2   ------->      CH3OH  
                                 1 mol                                        1 mol
                                2.66 mol                                    2.66 mol

4) We have 2.66 mol CH3OH
Molar mass CH3OH : M(CH3OH) = 12.0 +  4*1.0 + 16.0 = 32.0 g/mol

2.66 mol CH3OH * 32.0 g CH3OH/ 1 mol CH3OH =  85.12 g CH3OH
<span>
Answer is </span>D) 85.12 grams.
3 0
3 years ago
Other questions:
  • Which one of the following is a pure substance? 1.milk2. Concrete3. Wood 4. Salt water5. Elemental copper
    5·1 answer
  • Can someone help, like I need an answer now ಥ‿ಥ​
    14·1 answer
  • Consider the reaction Cl 2(g) + Br 2(g) &lt;=&gt; 2 BrCl(g), which is endothermic as written. What would be the effect on the eq
    10·2 answers
  • Tell me what happens during Observing a chemical change
    11·1 answer
  • Which is a potential benefit of genetic engineering in agriculture​
    10·1 answer
  • ANYONE KNOW CHEMISTRY.............................,..
    12·1 answer
  • Determine the oxidation number of the element that is underlined within the compound. BaCrO4 (Cr is underlined)
    10·2 answers
  • If 10.28 g of Cu(NO3)2 are obtained from the reaction of 4.54 g of Cu with excess HNO3, what is the percent yield of the reactio
    15·1 answer
  • Using the average atomic masses given inside the front cover of this book, calculate the number of atoms present in each of the
    5·1 answer
  • Is VAL ("23")+5=28? It is a true and false question.​
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!