Brainiest and 10 Points
What is the name of the rays the human eye can see?
A. Radio Rays
B. Water Waves
C. Visible Light Rays
D. X Rays

Answer:

3

Explanation:

potassium is a highly electropositive metal with one electron for bonding, it reacts with a highly electro negative non metal like chlorine to give an electrovalent or ionic bonding

The correct question is: 10 kg of R-134a at 300 kPa fills a rigid container whose volume is 14 L. Determine the temperature and total enthalpy in the container. The container is now heated until the pressure is 600 kPa. Determine the temperature and total enthalpy when the heating is completed.

Answer: The temperature is [tex]21.6^{o}C[/tex] and total enthalpy when the heating is completed is 300 kJ.

Explanation:

Given: Mass = 10 kg

Volume = 14 L

Final pressure = 600 K

First, convert volume from L to [tex]m^{3}/kg[/tex] as follows.

[tex]v_{1} = \frac{14 \times 10^{-3}}{10}\\= 0.0014 m^{3}/kg[/tex]

According to the R-134a tables at 300 kPa and [tex]0.0014 m^{3}/kg[/tex].

[tex]h_{1}[/tex] = 54.6 kJ/kg

[tex]T_{sat}[/tex] = 0.7 C

[tex]u_{1}[/tex] = 54.1 kJ/kg

Now, at the state 2 [tex]p_{2}[/tex] = 600 kPa and [tex]v_{2} = v_{1} = 0.0014 m^{3}/kg[/tex]

This means that the final temperature at state 2 is [tex]T_{2} = T_{sat} = 21.6^{o}C[/tex]

Hence, the change in enthalpy is calculated as follows.

[tex]\Delta H = m(h_{2} - h_{1})\\= 10(84.6 - 54.6)\\= 300 kJ[/tex]

The first law is applied to transfer the heat transfer as follows.

[tex]Q = m(u_{2} - u_{1})\\= 10(83.8 - 54.1) kJ\\= 297 kJ[/tex]

Thus, we can conclude that the temperature is [tex]21.6^{o}C[/tex] and total enthalpy when the heating is completed is 300 kJ.

Answer:

There is one valence electron in a neutral lithium atom.

Explanation:

The number of valence electrons in a neutral lithium atom is equal to one.

Valence electrons can be described as the electrons filling the outermost shell of an atom while the electrons in the inner shell of an atom are known as core electrons. Lewis structures are used to determine the number of valence electrons and know the types of chemical bonds.

Valence electrons of an atom can be filled in the same or different orbitals and these electrons are responsible for the interaction between atoms and cause the formation of chemical bonds.

Only electrons occupied in the outermost shell can participate in the formation of a bond or a molecule and are responsible for the reactivity of the element.

The number of electrons in the neutral atom of lithium is 3. There is only one electron present on the outermost shell 2s-orbital.

Learn more about valence electrons, here:

brainly.com/question/18612412

#SPJ5

Answer:

Sulphide ion(S-²) has a -2 charge

Ammonium (NH4+¹) has a +1 charge

When Exchange of Radicals Occur..

The compound formed is

(NH4)2S.

OPTION A IS YOUR ANSWER!

Answer:

NH4)2S

So it is A

Explanation:

Explanation:

Have a good luck with ur exam

Answer:

chlorous acid

Explanation:

The acidic equilibrium of weak acids, HX, occurs as follows:

HX ⇄ H+ + X-

Where Ka is written as:

Ka = [H+] [X-] / [HX]

The strongest acid is the acid that produce more H+. The acid with the higher Ka is the acid that produce more [H+] and is, thus, the strongest acid.

The higher Ka is the Ka of chlorus acid = 1.2x10-2

Right answer is:

Answer:

chlorous acid :)

Explanation:

Today, as part of the series of posts on soils, we are going to look at ‘soil texture’. Soil forms the basis for all life but it’s important to know about its mineral constitution as well as its biological profile.

Texture refers to the ‘feel’ of the soil. This is affected by the constituent materials found within it, specifically sand, silt and clay particles. A coarse sand will feel gritty but a wet clay will feel heavy and sticky. The texture of a soil has a direct impact on the way the soil reacts to certain environmental conditions – for example, towards drought or heavy rain (with sandy soils more freely draining).

There is a big difference in the size of the different particles.

Coarse sand = diameter 2-0.2mm

Fine sand = diameter 0.2-0.02mm

Silt = diameter 0.02-0.002mm

Clay = diameter less than 0.002mm

Note how the clay particles are much smaller than the sand particles – this is important as it means the total surface area of a clay soil is much greater and so the capacity to hold water is also much greater.

Between the sand, silt and clay particles there are lots of pores. In fact a soil as a whole is generally 45% mineral, 5% organic matter (depending on the soil) and 50% pore space through which air and water can pass.

Sand –

Made up of weathered primary rock minerals.

The particles are irregular in outline.

They are large and so do not pack together easily.

Large pore spaces in between.

Air gets in very easily and water flows rapidly through it.

Silt –

Answer:

5.9 g

Explanation:

Step 1: Write the balanced reaction for the photosynthesis

6 CO₂ + 6 H₂O ⇒ C₆H₁₂O₆ + 6 O₂

Step 2: Calculate the moles of CO₂

We have 5.0 L of CO₂ at 32 °C (305 K) and 750 mmHg. We can calculate the moles of CO₂ using the ideal gas equation.

P × V = n × R × T

n = P × V/R × T

n = 750 mmHg × 5.0 L/(62.4 mmHg.L/mol.K) × 305 K = 0.20 mol

Step 3: Calculate the moles of C₆H₁₂O₆ produced from 0.20 moles of CO₂

The molar ratio of CO₂ to C₆H₁₂O₆ is 6:1. The moles of C₆H₁₂O₆ produced are 1/6 × 0.20 mol = 0.033 mol

Step 4: Calculate the mass corresponding to 0.033 moles of C₆H₁₂O₆

The molar mass of C₆H₁₂O₆ is 180.16 g/mol.

0.033 mol × 180.16 g/mol = 5.9 g

Answer:

Hi, there your answer is A. As the frequency of a wave increases, the shorter its wavelength is.

Explanation:

When frequency increases, wavelength decreases.

Hope this Helps :)

Answer:

Explanation

i k the ansewer

Answer:

pH = 2.66

Explanation:

First we calculate the number of moles of each reactant, using the given volumes and concentrations:

We calculate how many acetic acid moles remain after the reaction:

We now calculate the molar concentration of acetic acid after the reaction:

27.5 mmol / (50.0 mL + 10.0 mL) = 0.458 M

Then we calculate [H⁺], using the following formula for weak acid solutions:

Finally we calculate the pH:

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]d = \frac{m}{v} \\ [/tex]

We have

[tex]d = \frac{1.25 \times {10}^{2} }{51} \\ = 2.45098..[/tex]

We have the final answer as

Hope this helps you

Answer:

approximately 15.1 grams.

Explanation:

The key to chemistry is to change everything to moles. Then when you have the answer in moles change the answer back to grams, liters, or whatever you want.

change 25 grams of potassium chlorate to moles.

calculate the gram molecular mass of potassium chlorate.

Chlorate is Cl with 3 oxygens. ate = saturated. Chlorine has seven valance electrons when it is saturated six of these electrons are used by oxygen ( 2 electrons per oxygen) leaving only 1 electron.

1 K x 39 grams/mole

+1 Cl x 35.4 grams/ mole

+3 O x 16 grams/ mole

= 122.4 grams / mole Potassium Chlorate

25

122.4

= moles.

2.05 moles of Potassium Chlorate.

There is a 1:1 mole ratio. 1 mole of Potassium Chlorate will produce 1 mole of Potassium Chloride.

2.05 moles of Potassium Chlorate will produce 2.05 moles of Potassium Chloride.

Find the gram molecular mass of Potassium Chloride.

1 K x 39 = 39

+1 Cl x 35.4 = 35.4

= 74.4 grams / mole.

2.05 moles x 74.4 grams/ mole = 15.2 grams

Answer:

idont know nalimotan ko hhhh...

Answer:

circulatory and excretory

Answer:

the correct answer is 12 sides (:

Explanation:

Answer:

sorry don't know the answer!!!

The question is incomplete, the complete question is;

Assume that your empty crucible weighs 15.98 g, and the crucible plus the sodium bicarbonate sample weighs 18.56 g. After the first heating, your crucible and contents weighs 17.51 g. After the second heating, your crucible and contents weighs 17.50 g.

What is the theoretical yield of sodium carbonate?

What is the experimental yield of sodium carbonate?

What is the percent yield for sodium carbonate?

Which errors could cause your percent yield to be falsely high, or even over 100%?

Answer:

See Explanation

Explanation:

We have to note that water is driven away after the second heating hence we are concerned with the weight of the pure dry product.

Hence;

From the reaction;

2 NaHCO3 → Na2CO3(s) + H2O(l) + CO2(g)

Number of moles of  sodium bicarbonate = 18.56 - 15.98 = 2.58 g/87 g/mol

= 0.0297 moles

2 moles of sodium bicarbonate yields 1 mole of sodium carbonate

0.0297 moles of 0.015 moles  sodium bicarbonate yields 0.0297 * 1/2 = 0.015 moles

Theoretical yield of sodium carbonate = 0.015 moles * 106 g/mol = 1.59 g

Experimental yield of sodium bicarbonate = 17.50 g - 15.98 g = 1.52 g

% yield = experimental yield/Theoretical yield * 100

% yield = 1.52/1.59 * 100

% yield = 96%

The percent yield may exceed 100% if the water and CO2 are not removed from the system by heating the solid product to a constant mass.

Answer:

874.89 mmHg

Explanation:

Using the combined gas law equation as follows:

P1V1/T1 = P2V2/T2

Where;

P1 = initial pressure (mmHg)

P2 = final pressure (mmHg)

V1 = initial volume (L)

V2 = final volume (L)

T1 = initial temperature (K)

T2 = final temperature (K)

Based on the information provided in this question;

P1 = 950 mm Hg

P2 = ?

V1 = 25 L

V2 = 30 L

T1 = 155°C = 155 + 273 = 428K

T2 = 200°C = 200 + 273 = 473K

Using P1V1/T1 = P2V2/T2

950 × 25/428 = P2 × 30/473

23750/428 = 30P2/473

55.49 = 0.063P2

P2 = 55.49 ÷ 0.063

P2 = 874.89 mmHg

Explanation:

Take shelter in a hard wall building

Close doors and windows cut off ventilation

Answer: A balanced chemical equation, including physical state symbols, for the decomposition of solid sodium azide ([tex]NaN_{3}[/tex]) into solid sodium and gaseous dinitrogen is [tex]2NaN_{3}(s) \rightarrow 2Na(s) + 3N_{2}(g)[/tex].

Explanation:

A chemical equation which contains same number of atoms on both reactant and product side is called a balanced chemical equation.

For example, [tex]NaN_{3}(s) \rightarrow Na(s) + N_{2}(g)[/tex]

Here, number of atoms present on reactant side are as follows.

Number of atoms present on product side are as follows.

To balance this equation, multiply [tex]NaN_{3}[/tex] by 2 on reactant side. Also, multiply Na by 2 and [tex]N_{2}[/tex] by 3 on product side.

The equation will be rewritten as follows.

[tex]2NaN_{3}(s) \rightarrow 2Na(s) + 3N_{2}(g)[/tex]

This equation contains same number of atoms on both reactant and product side. Hence, this equation is now balanced.

The symbols (s) and (g) depicts the physical state of substances present in the equation as solid and gas.

Thus, we can conclude that balanced chemical equation, including physical state symbols, for the decomposition of solid sodium azide ([tex]NaN_{3}[/tex]) into solid sodium and gaseous dinitrogen is [tex]2NaN_{3}(s) \rightarrow 2Na(s) + 3N_{2}(g)[/tex].

Answer:

a. 6 grams

b. 108 grams

c. 2 grams

d. 54 grams

Answer:

Rutherford used scientific investigation to study atoms.

Scientist who used scientific investigations to study atoms is Rutherford.

Atoms are the basic fundamental or functional unit of any substance present in the nature.

Rutherford is also known as the father of nuclear physics and he did scientific investigation on the massive part of atom called nucleus he discovered that there are two types of radiation, coming from the uranium atom are alpha and beta particles.

Scientific investigation is a method in which scientist will study, perform and observe results for the experiment.

Hence Rutherford used scientific investigation.

To know more about Scientific investigation, visit the below link:
https://brainly.com/question/17216882

Light energy travels in the form of waves.

could you theoretically cook methamphetamine? just wonderkng.

Answer:

Explanation:

The pH of a solution can be found by using the formula

[tex]pH = - log [ { H}^{+}][/tex]

From the question we have

[tex]ph = - log(9.25 \times {10}^{ - 5} ) \\ = 4.03385[/tex]

We have the final answer as

Hope this helps you

Answer:

Nitrogen molecule (N2)

The electronic configuration of nitrogen (Z=7) = 1s2 2s2 2px12py12pz1.

The total number of electrons present in the nitrogen molecule (N2) is 14.

In order to maximize energy, these 14 electrons can be accommodated in the different molecular orbitals.

N2: KK'(σ2s)2 (σ*2s)2 (π2Px)2 (π2py)2 (σ2pz)2

Here (σ1s)2 (σ*1s)2 part of the configuration is abbreviated as KK’, which denotes the K shells of the two atoms. In calculating bond order, we can ignore KK’, as it includes two bonding and two antibonding electrons.

The bond order of N2can be calculated as follows:

Here, Nb = 10 and Na = 4

Bond order = (Nb−Na) /2

B.O = (10−4)/2

B.O = 3

So your answer should be C3.

Answer:

Total pressure of the mixture = 1 atm

Partial pressure of He = 0.863 atm

Partial pressure of Ar  = 0.0173 atm

Partial pressure of Ne = 0.1197 atm

We confirm that the sum of partial pressure of each gas valu

Explanation:

STP conditions are:

1 atm of pressure and

273K of T°

We can also say that those value reffers to 1 mol.

We determine the moles of each:

5 g . 1mol / 4g = 1.25 moles of He

1g . 1mol / 39.9 g = 0.0250 moles of Ar

3.5g . 1mol / 20.18 g = 0.173 moles of Ne

Total pressure of a mixture can be obtained from the Ideal Gases Law.

P . V = n . R . T

Total moles: 1.25 + 0.025 + 0.173 = 1.448 moles

But now, we need the volume. We know that 1 mol is contained at 22.4L at STP.

1.448 mol . 22.4L / 1 mol = 32.4 L

That's the volume for our mixture. We replace:

32.4 L . P  = 1.448 mol . 0.082 . 273K

P = (1.448 mol . 0.082 . 273K) / 32.4L = 1 atm

Now we can obtained the partial pressure of each gas from mole fraction

Mol of gas / Total pressure = Partial pressure of gas / Total pressure

Partial pressure of He = (1.25 / 1.448) . 1 atm = 0.863 atm

Partial pressure of Ar = (0.025 / 1.448) . 1 atm = 0.0173 atm

We know that sum of partial pressure is 1 - (Mole fraction He + Mole fr. Ar)

Partial pressure of Ne = 1 - (0.863 + 0.0173) = 0.1197 atm

We confirm that the sum of partial pressure of each gas values the total pressure of the mixture: 0.863 + 0.0173 + 0.1197 = 1