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it's due today

Answer:

See explanation

Explanation:

The melting point range of a pure compound is about 1-2ºC of the expected melting point. An impure solid melts within a range   that is both larger than that of the pure substance  (>1ºC) and begin at a  lower temperature because impurities decrease the meting point. A melting range of 5º or more  indicates that a compound is impure.

Since the melting points of A and B are estimated  at 133 o C, the melting point range for each pure substance must be slightly different from each other. The melting point of the unknown is measured and its range is compared with the melting point ranges of pure A and B then decision can  now be made about the identity of the unknown solid.

Answer:

a) O2, Pt, Rh

b) Rb, Y, Sm, Mn, Sn, Li

c)Rb

Explanation:

We must consider the reduction potentials of each of the species in the question.

In (a) above, all the elements whose reduction potential is higher than the redox potential for the oxidation of I^- will react with a solution of I^- to generate I2 as shown above.

In (b) above, all the strong reducing agents can donate electrons to Ag^+ and reduce it to Ag as shown above.

In (c) Rb has a more negative reduction potential than sodium hence it can react with a solution of sodium salt to generate sodium metal.

Answer

512kj/mole

Explanation:

What is the work function of gold metal in kJ/mol if light with λ = 234 nm is necessary to eject electrons?

The energy can be calculated using below expresion;

E = hc/λ

Where h= planks constant= 6.626 x 10^-34

c= speed of light= 3 x 10^

λ= wavelength

hc= (6.626 x 10^-34 x 3 x 10^ 8)

=

Answer: The volume at an altitude of 20.0 km is 34.5289 L

Explanation:

Boyle's Law: This law states that pressure is inversely proportional to the volume of the gas at constant temperature and number of moles.

[tex]P\propto \frac{1}{V}[/tex]     (At constant temperature and number of moles)

[tex]P_1V_1=P_2V_2[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas = 101.325 kPa ( at sea level)

[tex]P_2[/tex] = final pressure of gas = 10 kPa

[tex]V_1[/tex] = initial volume of gas = 3.40774 L

[tex]V_2[/tex] = final volume of gas = ?

Now put all the given values in the above equation, we get the final volume of gas.

[tex]101.325\times 3.40774=10\times V_2[/tex]

[tex]V_2=34.5289L[/tex]

Thus the volume at an altitude of 20.0 km is 34.5289 L

Therefore, the final pressure of the gas will be 3.75 atm

The procedure that Dr. Simmons will not include as part of her scientific experiment is uncontrolled variables.

When a scientific investigation is carried out, experiments are used as a method of verifying results. Generally, when an experiment is carried out, you want to verify that given circumstances generate a specific result.

The experiments must be as controlled as possible so that they can be repeated and thus create reliable laws. Therefore, Dr. Simmons will not include uncontrolled variables in her experiment, because these variables can modify the result of an investigation in many ways and limit the production of new knowledge.

Uncontrolled variables are generally not included in scientific investigations because they cannot be modified and they influence various results that cannot be considered reliable knowledge.

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pH of buffer solution : 4.32

A buffer solution is a solution that can maintain a good pH value due to the addition of a little acid or a little base or dilution.

The buffer solution can be acidic or basic

Acid buffer solutions consist of weak acids(H₂CO₃) and their salts.(NaHCO₃)

mol H₂CO₃

[tex]\tt 0.032\times 0.25=0.008[/tex]

mol NaHCO₃

[tex]\tt 0.02\times 0.15=0.003[/tex]

[tex]\tt [H^+]=Ka\dfrac{mole~weak~acid}{mole~salt}\\\\(H^+]=1.8\times 10^{-5}\dfrac{0.008}{0.003}=4.8\times 10^{-5}\\\\pH=5-log~4.8=4.32[/tex]

Answer: ghfbg

Explanation: fgfghfg

Answer: CH4

Explanation:

BRAINLESS PLEASE

Answer:

O₂

Explanation:

The example of the compound or the molecule that forms a non-polar bond is oxygen gas.

Oxygen gas has a formula of O₂

Answer:

It lights on fire

Explanation:

The friction sparks the match causing it to go on fire.

Answer: d

Explanation:

On edg

Answer:

Hey! I'll help you.

Explanation:

I got your back.

Answer:

hjhjhjhhhhh

Explanation:

Answer:

1.089%

Explanation:

From;

ν =1/2πc(k/meff)^1/2

Where;

ν = wave number

meff = reduced mass or effective mass

k = force constant

c= speed of light

Let

ν =1/2πc (k/meff)^1/2  vibrational wave number for 23Na35 Cl

ν' =1/2πc(k'/m'eff)^1/2 vibrational wave number for 23Na37 Cl

The between the two is obtained from;

ν' - ν /ν  = (k'/m'eff)^1/2 - (k/meff)^1/2 / (k/meff)^1/2

Therefore;

ν' - ν /ν = [meff/m'eff]^1/2 - 1

Substituting values, we have;

ν' - ν /ν = [(22.9898 * 34.9688/22.9898 + 34.9688) * (22.9898 + 36.9651/22.9898 * 36.9651)]^1/2  -1

ν' - ν /ν = -0.01089

percentage difference in the fundamental vibrational wavenumbers of 23Na35Cl and 23Na37Cl;

ν' - ν /ν * 100

|(-0.01089)|  × 100 = 1.089%

Answer:

1.089%

Explanation:

From;

ν =1/2πc(k/meff)^1/2

Where;

ν = wave number

meff = reduced mass or effective mass

k = force constant

c= speed of light

Let

ν =1/2πc (k/meff)^1/2  vibrational wave number for 23Na35 Cl

ν' =1/2πc(k'/m'eff)^1/2 vibrational wave number for 23Na37 Cl

The between the two is obtained from;

ν' - ν /ν  = (k'/m'eff)^1/2 - (k/meff)^1/2 / (k/meff)^1/2

Therefore;

ν' - ν /ν = [meff/m'eff]^1/2 - 1

Substituting values, we have;

ν' - ν /ν = [(22.9898 * 34.9688/22.9898 + 34.9688) * (22.9898 + 36.9651/22.9898 * 36.9651)]^1/2  -1

ν' - ν /ν = -0.01089

percentage difference in the fundamental vibrational wavenumbers of 23Na35Cl and 23Na37Cl;

ν' - ν /ν * 100

|(-0.01089)|  × 100 = 1.089%

Answer:

c) H2O and HSO4-

Explanation:

The dehydration of 2-methylcyclohexanol occurs in the presence of H2SO4. Recall that acids are proton donors in solution; the equilibrium shown below is then set up,

H2SO4(aq)  +  H2O(l) ⇄H3O^+(aq) + HSO4^-(aq)

The species H2O and HSO4- are two proton acceptors in the system. According to the Brownstead- Lowry definition, a base is a proton acceptor in solution.

Hence H2O and HSO4- are bases present in the dehydration of 2-methylcyclohexanol.

Answer:

Increases

Explanation:

Frequency and wavelength of lights are inversely proportional to each other.

The wave of light having highest frequency have shortest wavelength and the light with the shortest frequency having highest wavelength.

Formula:

Speed of light = wavelength × frequency

c = λ × f

λ = c/f

This formula shows that both are inversely related to each other.

The speed of light is 3×10⁸ m/s

Frequency is taken in Hz.

It is the number of oscillations, wave of light make in one second.

Wavelength is designated as "λ" and it is the measured in meter. It is the distance between the two crust of two trough.

Answer:

The correct answer is - Amplitude.

Explanation:

Frequency modulation is a method or procedure that sends or transmits the signals such as radio broadcasting, telecommunication where the value of the transmitted signal is provided by the frequency of a high-frequency wave that carries the signal.

In this method of encoding the information, the amplitude of the carrier remains the same or constant but frequency varies in accordance with the modulating signal.

Answer:

The answer is C Amplitude

Explanation:

Because you can give me Brainiest  PLZZZZZZZZZZZZZZZZZZZZ

Answer:

Carbohydrates

Explanation:

Answer:

Tollen's test or silver mirror test is use to distinguish between ketone and aldehyde.

Explanation:

Tollen's test is use to distinguish aldehyde from ketone because Tollen reagent consist of silver nitrate and ammonia and it oxidized aldehydes to carboxylic acid and the silver Ag+ is reduced to solid silver Ag. It form a inner film wall on the tube that look like mirror. Ketone do not react with Tollen reagent and therefore does not form silver mirror on the tube wall.

Answer:

Total gas pressure is 1.60 atm

Explanation:

To solve this question we can use the Ideal Gases Law. We need to determine how many moles of each gas will be finally present at the flask of 7 L.

Let's asume the gas, are at Asbsolute T°, 273K

P. V = n . R . T

3.5 atm . 2L = n . 0.082 . 273K

(3.5 atm . 2L) / (0.082 . 273K) = 0.313 moles

(2.8 atm . 1.5L) / (0.082 . 273K) =  0.188 moles

Total moles = 0.313 mol + 0.188 mol = 0.501 mol

Let's calcualte the hole pressure

P . 7L = 0.501 moles . 0.082 . 273K

P = (0.501 moles . 0.082 . 273K) / 7L → 1.60 atm

Answer:

vinegar and soap

Explanation:

Answer:

vinegar and soap

Explanation: just took the test

Answer:it’s A and B

Explanation:

Answer:

A and B

Explanation:

They’re both fusion.

Answer:

ether group

Explanation: I looked it up

sorry but I need some three point so that's why I didn't

Answer:

1. FASTER THAN- #2

2. WARMER THAN #1

3. OCCUR FROM SUBSTANCE B TO SUBSTANCE A- #3

Explanation:

I did the assignment On edg And got it right

Answer:

Use the image to complete the sentences.  

At left a grid labeled A of regularly arranged orange balls with small movement lines near each. At right a grid labeled B of regularly arranged orange balls with large movement lines near each.

Two different substances, Substance A and Substance B, are in direct contact with each other and are at different temperatures.

The particles in Substance B are vibrating

✔ faster than

the particles in Substance A. This means Substance B is

✔ warmer than

Substance A and conduction will

✔ occur from Substance B to Substance A

.

Explanation:

I know im late

Answer:

Check explanation section.

Explanation:

In order to be able to answer this question accurately,there is need to follow the formula below for the calculation;

Numbers of decades = total volume/ volume per decade. ----------------------(1).

So, we are given from the Question above that the volume of water in Lake Michigan = 13 billion gallons of water.

And if chicago uses 5 million gallons of water every decade.

Therefore, using the formula (1) above, we have;

Numbers of decades = 13 × 10^9/ 5 × 10^6 = 2.6 × 10^15 decades.

Answer:

a) 0.03050 = 3.050 × 10-²

b) 0.256 x 10°= 2.56 × 10-¹

c) 25.005 10 =​ 2.500510 × 10¹

Explanation:

Scientific notations is a way of making very large or very small numbers more comprehensive or simplified. It involves the use of power of ten (10^). The numbers are represented to the power of ten. The following format is used:

a x 10^b

where; a is a number or decimal number between 1 and 10 i.e less than 10 but greater than 1

b is the power of ten

To write a number in scientific notation,

- we move the decimal point right or left depending on whether we're trying to reduce or increase the number

- we count the number of times the decimal point was moved. This serves as the b in the format above.

For example,

a) 0.03050 = 3.050 × 10-²

The decimal point was moved rightward twice. This caused the ^-2 power.

b) 0.256 x 10°= 2.56 × 10-¹

The decimal point was moved rightward once. This caused the ^-1 power.

c) 25.005 10 =​ 2.500510 × 10¹

The decimal point was moved leftward once. This caused the ^1 power.

Answer:

747mL of the 0.157mL are needed

Explanation:

To find the grams of salt we need to convert these grams to moles using molar mass of magnesium nitrate (148.3g/mol). Then, with the molar concentration we can convert the moles to liters and, as last, to milliliters, as follows:

Moles Mg(NO₃)₂:

17.4g * (1mol / 148.3g) = 0.117 moles of magnesium nitrate

Volume:

0.117 moles * (1L / 0.157moles) = 0.747L

= 747mL of the 0.157mL are needed

In a 0.157M solution there are 0.157 moles per liter of solution

Answer:

it should be a base

Explanation:

this is because solutions such as bleach are usually slippery on the hands, and mostly bases are in cleaning solutions

Answer:

2HBr + O2 = H20 +Br2

Explanation:

Answer:

4hbr(aq) + O2(g) = 2H2O + 2Br2

Explanation: