answer.
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
Romashka-Z-Leto [24]
2 years ago
6

A magnesium ion, Mg2+, with a charge of 3.2×10−19C and an oxide ion, O2−, with a charge of −3.2×10−19C, are separated by a dista

nce of 0.25 nm. How much work would be required to increase the separation of the two ions to an infinite distance?
Chemistry
1 answer:
baherus [9]2 years ago
7 0

Explanation:

Formula for work done is as follows.

           W = -k \frac{q_{1}q_{2}}{d}    

where,  k = proportionality constant = 8.99 \times 10^{9} Jm/C^{2}

            q_{1} = charge of Mg^{2+} = 3.2 \times 10^{-19} C

            q_{2} = charge of O_{2-} = -3.2 \times 10^{-19} C

            d = separation distance = 0.45 nm = 0.45 \times 10^{-9} m

Now, we will put the given values into the above formula and calculate work done as follows.

         W = -k \frac{q_{1}q_{2}}{d}    

           = \frac{-[8.99 \times 10^{9} Jm/C^{2} \times 3.2 \times 10^{-19} C \times -3.2 \times 10^{-19} C]}{0.25 \times 10^{-9} m}  

           = 3.68 \times 10^{-18} J

Thus, we can conclude that work required to increase the separation of the two ions to an infinite distance is 3.68 \times 10^{-18} J.

You might be interested in
On top of one of the peaks in rocky mountain national park the pressure of the atmosphere is 550 torr determine the boiling poin
Dahasolnce [82]

Answer:

The boiling point of water at 550 torr will be 91 °C or 364 Kelvin

Explanation:

Step 1: Data given

Pressure = 550 torr

The heat of vaporization of water is 40.7 kJ/mol.

Step 2: Calculate boiling point

⇒ We'll use the Clausius-Clapeyron equation

ln(P2/P1) = (ΔHvap/R)*(1/T1-1/T2)

ln(P2/P1) = (40.7*10^3 / 8.314)*(1/T1 - 1/T2)

⇒ with P1 = 760 torr = 1 atm

⇒ with P2 = 550 torr

⇒ with T1 = the boiling point of water at 760 torr = 373.15 Kelvin

⇒ with T2 = the boiling point of water at 550 torr = TO BE DETERMINED

ln(550/760) = 4895.4*(1/373.15 - 1/T2)

-0.3234 = 13.119 - 4895.4/T2

-13.4424= -4895.4/T2

T2 = 364.2 Kelvin = 91 °C

The boiling point of water at 550 torr will be 91 °C or 364 Kelvin

4 0
2 years ago
Write a balanced equation for the transmutation that occurs when a scandium-48 nucleus undergoes beta decay.
Tju [1.3M]

Answer:

A scandium-48 nucleus undergoes beta-minus decay to produce a titanium-48 nucleus.

\rm ^{48}_{21}Sc \to ^{48}_{22}Ti + ^{\phantom{1}\,0}_{-1}e^{-} + \bar{\mathnormal{v}}_e.

Explanation:

There are two types of beta decay modes: beta-minus and beta-plus.

In both decay modes, the mass number of the nucleus stays the same.

However, in a beta-minus decay, the atomic number of the nucleus increases by one. In a beta-plus decay, the atomic number decreases by one.

Each beta-minus decay releases one electron and one electron antineutrino. Each beta-plus decay releases one positron and one electron neutrino.

Look up the atomic number and relative atomic mass for the element scandium.

  • The atomic number of \rm Sc is 21.
  • The relative atomic mass of \rm Sc is approximately 45.0.

This question did not specify whether the decay here is beta-plus or a beta-minus. However, the relative atomic mass of this element can give a rough estimate of the mode of decay.

Each element (e.g, \rm Sc) can have multiple isotopes. These isotopes differ in mass. The relative atomic mass of an element is an average  across all isotopes of this element. This mass is weighted based on the relative abundance of the isotopes. Its value should be closest to the most stable (and hence the most abundant) isotope.

The mass number of scandium-48 is significantly larger than the relative atomic mass of this element. In other words, this isotope contains more neutrons than isotopes that are more stable. There's a tendency for that neutron to convert to a proton- by beta-minus decay, for example.

The atomic number of the nucleus will increase by 1. 21 + 1 = 22. That corresponds to titanium. The mass number stays the same at 48. Hence the daughter nucleus would be titanium-48. Note that two other particles: one electron and one electron \rm e^{-} and one antineutrino \bar{v}_{\text{e}} (note the bar.) The neutrino helps balance the lepton number of this reaction.

6 0
2 years ago
Which of the following are elements, which are molecules but not compounds, which are compounds but not molecules, and which are
andreev551 [17]

Explanation:

Molecules of compounds are are compounds composed two or more than two different elements.

Molecules of an elements are made up two or more than two numbers of same type of atoms

(a) SO_2

It is compound composed of sulfur and oxygen element.

(b) S_8

It is a molecules of a single element made up of 8 sulfur atoms.

(c) Cs

It is a symbol of an element named cesium.

(d) N_2O_5

It is compound composed of nitrogen and oxygen element.

(e) O

It is a symbol of an element named oxygen.

(f) O_2

It is a molecule of a single element made up of 2 oxygen atoms.

(g) O_3

It is a molecule of a single element made up of 3 oxygen atoms.

(h)CH_4

It is compound composed of carbon and hydrogen element.

(i) KBr

It is compound composed of potassium and bromine element.

(j) S

It is a symbol of an element named sulfur.

(k) P_4

It is a molecule of a single element made up of 4 phosphorus atoms.

(l) LiF

It is compound composed of lithium and fluorine element.

4 0
2 years ago
Read 2 more answers
Nicole has 2 glasses on the counter: one of water and one of sugar. She is baking a cake and needs to use the sugar-water for th
Schach [20]

Answer:It is a mixture

Explanation:

If it is pure sugar it’s neither but if it has water it is a homogeneous mixture

8 0
2 years ago
Read 2 more answers
A 10.0-ml sample of 0.200 m hydrocyanic acid (hcn) is titrated with 0.0998 m naoh. what is the ph at the equivalence point? for
tatyana61 [14]
When the titration of HCN with NaOH is:

HCN (aq) + OH- (aq) → CN-(aq) + H2O(l)

So we can see that the molar ratio between HCN: OH-: CN- is 1:1 :1

we need to get number of mmol of HCN = molarity * volume 

                      = 0.2 mmol / mL* 10 mL = 2 mmol

so the number of mmol of NaOH = 2 mmol according to the molar ratio

so, the volume of NaOH = moles/molarity

                                          = 2 mmol / 0.0998mL

                                          = 20 mL

and according to the molar ratio so, moles of CN- = 2 mmol

∴the molarity of CN- =  moles / total volume 

                                   = 2 mmol / (10mL + 20mL ) = 0.0662 M

when we have the value of PKa = 9.31 and we need to get Pkb

so, Pkb= 14 - Pka

            = 14 - 9.31 = 4.69 

when Pkb = -㏒Kb

         4.69 = -㏒ Kb 

∴ Kb = 2 x 10^-5

and when the dissociation reaction of CN- is:

CN-(aq) + H2O(l) ↔ HCN(aq) + OH- (aq) 

by using the ICE table:

∴ the initials concentration are:

[CN-] = 0.0662 M

and [HCN] = [OH]- = 0 M

and the equilibrium concentrations are:

[CN-] = (0.0662- X)

[HCN] = [OH-]= X

when Kb expression = [HCN][OH-] /[CN-]

by substitution:

2 x 10^-5 = X^2 / (0.0662 - X)

X = 0.00114 

∴[OH-] = X = 0.00114

when POH = -㏒[OH]

                    = -㏒ 0.00114

POH = 2.94

∴PH = 14 - 2.94 = 11.06



 

6 0
2 years ago
Other questions:
  • 58.5g of sodium iodide are dissolved in 0.5dm3. what concentration would this be?
    6·1 answer
  • Consider the hydrate FeSO4 • 7H2O.
    9·2 answers
  • How many significant figures the measurement have 56.0g 0.0004m 1003ml 0.0350s
    13·1 answer
  • A solid sample of a compound and a liquid sample of the same compound are each tested for electrical conductivity. which test co
    10·1 answer
  • Three 5-l flasks, fixed with pressure gauges and small valves, each contains 4 g of gas at 273 k. flask a contains h2, flask b c
    7·1 answer
  • Which of the following statements is true?
    7·2 answers
  • A radioactive nuclide is used to detect eye tumors. An atom of this radionuclide contains 15 protons, 15 electrons, and 17 neutr
    12·2 answers
  • Tracie measured 87.47 mg of cholesterol in 0.03 mL of blood. What is the density of this mixture in g/mL?
    5·1 answer
  • A sample of a substance has a mass of 4.2 grams and a volume of 6 milliliters. The density of this substance is
    5·2 answers
  • According to Valence Shell Electron Pair Repulsion (VSEPR) theory, which statement is correct? If a molecule has four pairs of e
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!