How do some insects take advantage of the surface tension of water?

Answer:

0.702 /s

Explanation:

Rate constant at [tex][298 \mathrm{~K}, \mathrm{~K}_{1}=3.46 \times 10^{-2} \mathrm{~s}^{-1}[/tex]

Rate constant at [tex]350 \mathrm{~K}, \mathrm{~K}_{2}=?[/tex]

[tex]T_{1}=298 \mathrm{~K}[/tex]

[tex]T_{2}=350 \mathrm{~K}[/tex]

Activation energy, [tex]\mathrm{Ea}=50.2 \times 10^{3} \mathrm{~J} / \mathrm{mol}[/tex]

Use the following equation to calculate [tex]K_{2}$ at $350 \mathrm{~K}[/tex]

Use the following equation to calculate [tex]K_{2}$ at $350 \mathrm{~K}[/tex]

[tex]\ln \frac{\mathrm{K}_{2}}{\mathrm{~K}_{1}}=\frac{\mathrm{Ea}}{\mathrm{R}}\left[\frac{1}{\mathrm{~T}_{1}}-\frac{1}{\mathrm{~T}_{2}}\right][/tex]

Therefore,

 [tex]\ln \left(\frac{K_{2}}{3.46 \times 10^{-2} \mathrm{~s}^{-1}}\right) &=\frac{50.2 \times 10^{3} \mathrm{~J} / \mathrm{mol}}{8.314 \mathrm{JK}^{-1} \mathrm{~mole}^{-1}}\left[\frac{1}{298 \mathrm{~K}}-\frac{1}{350 \mathrm{~K}}\right][/tex]

[tex]\ln \left(\frac{K_{2}}{3.46 \times 10^{-2} \mathrm{~s}^{-1}}\right) &=\frac{50.2 \times 10^{3} \mathrm{~J} / \mathrm{mol}}{8.314 \mathrm{JK}^{-1} \mathrm{~mole}^{-1}}\left[\frac{52 \mathrm{~K}}{298 \mathrm{~K} \times 350 \mathrm{~K}}\right][/tex]

[tex]\frac{K_{2}}{3.46 \times 10^{-2} \mathrm{~s}^{-1}} &=\mathrm{e}^{3.01}[/tex]

[tex]\frac{K_{2}}{3.46 \times 10^{-2} \mathrm{~s}^{-1}} &=20.3[/tex]

[tex]K_{2} &=20.3 \times 3.46 \times 10^{-2} \mathrm{~s}^{-1}[/tex]

[tex]&=0.702 \mathrm{~s}^{-1}[/tex]

hence, the rate constant at [tex]350 \mathrm{~K} [/tex] is 0.702[tex]\mathrm{~s}^{-1}[/tex]

Answer: The molar mass of the gas is 9.878 g/mol.

Explanation:

According to Graham's law, the rate of diffusion is inversely proportional to square root of molar mass of gas.

[tex]Rate = \frac{1}{\sqrt{M}}[/tex]

where,

M = molar mass of gas

As given gas diffuses 1/7 times faster than hydrogen gas. So, its molar mass is calculated as follows.

[tex]\frac{R_{1}}{R_{2}} = \sqrt{\frac{M_{2}}{M_{1}}}\\[/tex]

where,

[tex]M_{1}[/tex] = molar mass of hydrogen gas

[tex]M_{2}[/tex] = molar mass of another given gas

[tex]R_{1}[/tex] = rate of diffusion of hydrogen

[tex]R_{2}[/tex] = rate of diffusion of another given gas = [tex]\frac{1}{7}R_{1}[/tex]

Substitute the values into above formula as follows.

[tex]\frac{R_{1}}{R_{2}} = \sqrt{\frac{M_{2}}{M_{1}}}\\\frac{R_{1}}{\frac{1}{7}R_{1}} = \sqrt{\frac{M_{2}}{2}}\\7 \times 1.414 = M_{2}\\M_{2} = 9.878 g/mol[/tex]

Thus, we can conclude that the molar mass of the gas is 9.878 g/mol.

Answer:

98.78 g/mol

Explanation:

Just took the test

Answer:

A. 2AgI + Na2S → Ag2S + 2NaI

B. Na3PO4 + 3HCl → 3NaCl + H3PO4

C. Ba3N2 + 6H2O → 3Ba(OH)2 + 2NH3

D. TiCl4 + 2H2O → TiO2 + 4HCl

E. 3CaCl2 + 2Na3PO4 → Ca3(PO4)2 + 6NaCl

Explanation:

V2 = 276 ml

Explanation:

Given:

V1 = 250 ml V2 = ?

T1 = 293K. T2 = 324K

Here, we use Charles's law:

V1/T1 = V2/T2

Solving for P2, we get

V2 = (T2/T1)V1

= (324K/293K)(250 ml)

= 276 ml

Explanation:

Normally, fusion involves two heavy hydrogen nuclides but since we have 4 light hydrogen nuclides, two of which underwent positron emission, thus changing two protons into neutrons plus 2 positrons and 2 neutrinos. The resulting nucleus from this fusion reaction is an He-4 nucleus.

Solution :

[tex]$H_2 +I_2\rightleftharpoons 2HI$[/tex]

Initial concentration               Equilibrium concentration           [tex]$K_c=\frac{[HI]^2}{[H_2][I_2]}$[/tex]

  (mol/L)                                           (mol/L)

[tex]$[H_2]$[/tex]                 [tex]$[I_2]$[/tex]            [tex]$[HI]$[/tex]    [tex]$[H_2]$[/tex]                 [tex]$[I_2]$[/tex]            [tex]$[HI]$[/tex]

[tex]$2.4 \times 10^{-2}$[/tex]     [tex]$1.38 \times 10^{-2}$[/tex]  0     [tex]$1.14 \times10^{-2}$[/tex]    [tex]$0.12 \times 10^{-2}$[/tex]  [tex]$2.52 \times 10^{-2}$[/tex]        46.42

[tex]$2.4 \times 10^{-2}$[/tex]     [tex]$1.68 \times 10^{-2}$[/tex]  0     [tex]$0.92 \times10^{-2}$[/tex]    [tex]$0.20 \times 10^{-2}$[/tex]  [tex]$2.96 \times 10^{-2}$[/tex]        47.61

[tex]$2.4 \times 10^{-2}$[/tex]     [tex]$1.98 \times 10^{-2}$[/tex]  0     [tex]$0.77 \times10^{-2}$[/tex]    [tex]$0.31 \times 10^{-2}$[/tex]  [tex]$3.34 \times 10^{-2}$[/tex]        46.73

[tex]$2.4 \times 10^{-2}$[/tex]     [tex]$1.76 \times 10^{-2}$[/tex]  0     [tex]$0.92 \times10^{-2}$[/tex]    [tex]$0.22 \times 10^{-2}$[/tex]  [tex]$3.08 \times 10^{-2}$[/tex]        46.86

[tex]$0$[/tex]                  [tex]$0$[/tex]        [tex]$3.04 \times 10^{-2}$[/tex]     [tex]$0.345 \times10^{-2}$[/tex]    [tex]$0.345 \times 10^{-2}$[/tex]  [tex]$2.35 \times 10^{-2}$[/tex] 46.39

[tex]$0$[/tex]                  [tex]$0$[/tex]        [tex]$7.58 \times 10^{-2}$[/tex]     [tex]$0.86 \times10^{-2}$[/tex]    [tex]$0.86 \times 10^{-2}$[/tex]  [tex]$5.86 \times 10^{-2}$[/tex]     46.42

Average [tex]$K_c=46.738$[/tex]

Answer:

Explanation:

Step 1: Calculate the amount of sodium hydroxide in moles

Volume of sodium hydroxide solution = 25.0 ÷ 1,000 = 0.0250 dm3

Rearrange:

Concentration in mol/dm3 =

Amount of solutein mol = concentration in mol/dm3 × volume in dm3

Amount of sodium hydroxide = 0.100 × 0.0250

= 0.00250 mol

Step 2: Find the amount of hydrochloric acid in moles

The balanced equation is: NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

So the mole ratio NaOH:HCl is 1:1

Therefore 0.00250 mol of NaOH reacts with 0.00250 mol of HCl

Step 3: Calculate the concentration of hydrochloric acid in mol/dm3

Volume of hydrochloric acid = 20.00 ÷ 1000 = 0.0200 dm3

Concentration in mol/dm3 =

Concentration in mol/dm3 =

= 0.125 mol/dm3

Step 4: Calculate the concentration of hydrochloric acid in g/dm3

Relative formula mass of HCl = 1 + 35.5 = 36.5

Mass = relative formula mass × amount

Mass of HCl = 36.5 × 0.125

= 4.56 g

So concentration = 4.56 g/dm3

Answer:

one to one

Explanation:

Answer:

In the ionic solid sodium chloride, there is one to one ratio of sodium ions to chloride ions

Answer:

D ) Chemical Change

Explanation:

Answer:

A. 5.3 X 10^-2

Explanation:

I got 100 on PLATO

Carbon dioxide is released when limestone is heated during the production of [tex]\sf\purple{cement}[/tex]. ✔

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Answer:

friction

Explanation:

conduction doesn't really need much to start it. it basically has that reaction from the start so it's not conduction. Since heat is produced by friction in this situation it causes static to happen. so i think its friction

Answer:

17.6kg

Explanation:

mass = Volume × Density

mass = 5000cm^3 × 3.52g/cm^3

mass = 17600g = 17.6kg

Answer:

Electrical resistivity is a property of a material that tells you how much it resists the flow of electric current, while conductivity quantifies how easily current flows.

Answer:

.025 ml 02

Explanation:

I made a pdf and pasted it in and etc

Answer:

1. 0.0500 moles K, 0.0250 moles Cr and 0.1000 moles O.

2. 9.00 moles ammonium ions are present.

Explanation:

1. In 1mol of K2CrO4 there are 2 moles of K, 1 mole of Cr and 4 moles of O.

The moles in 0.0250 moles K2CrO4 are:

0.0250mol * 2 = 0.0500 moles K

0.0250mol * 1 = 0.0250 moles Cr

0.0250mol * 4 = 0.1000 moles O

2. In 1 mole of (NH4)2CO3 there are 2 moles of ammonium ions, NH₄⁺.

In 4,50 moles are:

4.50 moles * 2 = 9.00 moles ammonium ions are present

Answer:

BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

The activity of four unknown metals based on their chemical changes is option B.

Chemical changes are defined as changes which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical change.

There are several characteristics of chemical changes like change in color, change in state , change in odor and change in composition . During chemical change there is also formation of precipitate an insoluble mass of substance or even evolution of gases.

There are three types of chemical changes:

1) inorganic changes

2)organic changes

3) biochemical changes

During chemical changes atoms are rearranged and changes are accompanied by an energy change as new substances are formed.

Learn more about chemical change,here:

https://brainly.com/question/23693316

#SPJ3

Answer:

It is better to do chemistry

Explanation:

So that you will learn more of chemicals

Answer:

D.

Explanation:

Answer

0°C

Explanation:

substance be formed in it's solid state

Answer: water

Explanation: those elements all react to water , so the answer would be water . :)

Answer:

"0.24 J/g.k" is the appropriate solution.

Explanation:

Mass of substance,

m = 110.00 g

Heat,

q = 396 J

Change in temperature,

ΔT = 15.0°C  

Now,

The specific heat will be:

⇒  [tex]q=ms \Delta T[/tex]

On putting the given values, we get

⇒  [tex]396=110.00\times s\times 15.0[/tex]

⇒  [tex]396=s\times 1650[/tex]

⇒      [tex]s=\frac{396}{1650}[/tex]

⇒         [tex]=0.24 \ J/g.k[/tex]

What were Lamarck's ideas about evolution and Why were those ideas incorrect?

→ These and other examples show that Lamarck's theory does not explain how life formed and became the way it is. The other way that Lamarck's theory has been proven wrong is the study of genetics. Darwin knew that traits are passed on, but he never understood how they are passed on.

Answer:

The arrangement of electrons within an atom is called electron configuration

If I help you, will you help other people?

Actually "this is the worst question i've ever seen use the internet bud" why don't you do that.

Answer:

Ca^2+

Explanation:

As we know, more energy is required to remove an electron from a positively charged ion than is required to remove an electron from a neutral atom. Hence, the second ionization energy of calcium is greater than its first ionization energy.

However, the third and fourth ionization energies of calcium are much higher than the second ionization energy because they involve removal of electrons from an inner filed shell. This process requires a lot of energy and is often not feasible.

Hence, the most common ion of calcium must be Ca^2+ where only two electrons are removed from calcium.

Answer:

B. 2.2

Explanation:

Answer:

Electrons and protons are not positively charged

Explanation:

Neutrons are the only ones positively charged in the structure of an atom.... Also like charges repel which means a -ive and a - ive will repel when together

Answer:

The respiratory system is the network of organs and tissues that help you breathe. basically your airways, lungs, and blood vessels so you quite literally need these to survive I mean your muscles need oxygen to function and your brain needs oxygen to function so without your respiratory system you wouldn't be able to move much and you would quickly pass out and die from the lack of oxygen to your brain there are other body processes that need oxygen as well but these are just two examples.

Explanation:

Answer:

Maybe it’s dark ??????????????

Explanation:

Hm

Yes, potassium metal can be used to react with an acid to prepare a soluble salt.

Acids react with metals to yield the corresponding metal salt and hydrogen gas.

One of the properties of metals is their ability to react with dilute acids to yield  a soluble salt and hydrogen gas. This is a common reaction for all metals that are above hydrogen in the activity series.

Potassium can react with a hypothetical acid HB as follows;

2K(s) + 2HB(aq) ------> 2KB(aq) + H2(g)

https://brainly.com/question/6136372

Answer:

1045 J

Explanation:

By using the formula Eh= mass×specific heat capacity × change in tempreture

With it being a known fact that the specific heat capacity of water is 4.16g/j/°c