Answer:
ZnC4H10
Explanation:
The empirical formula of a compound refers to the formula that gives the simplest whole number ratio of each atoms of the elements in the compound.
The empirical formula is calculated thus:
The given percentages in the question represent the mass in grams of each element in the compound.
Zinc= 53%, C= 38.9%, H= 8.1% which represents 53g, 38.9g and 8.1g of each element respectively.
Molar Mass of Zn= 65.4 g/mol
Molar Mass of C= 12 g/mol
Molar Mass of H= 1 g/mol
Step 1: Divide the mass of each element by the molar mass given to convert to moles:
Zn= 53/65.4 = 0.81moles
C= 38.9/12 = 3.24moles
H= 8.1/1 = 8.1moles
Step 2: Divide each mole value by the smallest number of moles calculated, which is 0.81moles:
Zn= 0.81/0.81 = 1
C= 3.24/0.81 = 4
H= 8.1/0.81= 10
This is the mole ratio represented in the subscript of each element in the empirical formula:
That is, Zn (1) C (4) H (10)
Empirical formula= ZnC4H10
Chemical change example
Answer: burning paper
Explanation:
The paper burns in air to form smoke and ash. which makes it a chemical change.
Select the items that describe a chemical property below. Choose THREE correct answers.
1:Heated iron can be hammered into a sword.
2:A handwarmer gets warm when it is opened and exposed to air.
3:Propane ignites to heat a grill.
4:Cotton is dyed red to make a dress.
5:A cylinder in an engine uses gasoline to move pistons.
6:Maple syrup is thicker than water.
Answer:
2:A handwarmer gets warm when it is opened and exposed to air.
3:Propane ignites to heat a grill.
4:Cotton is dyed red to make a dress.
Explanation:
The definition of a chemical property is when a property of characteristic of a substance that is observed during a reaction in which a chemical has been changed
What is the atomic number of neon?
Answer:
the atomic number of a neon is 10
Determinación de pH Expresa las siguientes concentraciones de [H+ ] en función del pH • [H+] = 0.001 M • [H+] = 0.002 M • [H+] = 2.45X10-4 M • [H+] = 5.2X10-9 M • [H+] = 0.04 M
Answer:
• pH = 3.0
• pH = 2.70
• pH = 3.61
• pH = 8.28
• pH = 1.40
Explanation:
El pH es una medida en química usada para determinar el grado de acidez o basicidad en una solución.
Se define como:
pH = -log₁₀ [H⁺]
El - logaritmo de la concentración molar de H⁺
Para las concentraciones de H⁺ dadas:
• [H+] = 0.001 M
pH = -log (0.001M) = 3
pH = 3.0
• [H+] = 0.002 M
pH = -log (0.002M)
pH = 2.70
• [H+] = 2.45X10-4 M
pH = -log (2.45X10-4 M )
pH = 3.61
• [H+] = 5.2X10-9 M
pH = -log (5.2X10-9 M)
pH = 8.28
• [H+] = 0.04 M
pH = -log (0.04M)
pH = 1.40
Air is an example of a mixture because the elements and compounds that make up air retain their individual properties. T or F
Answer:
True
Explanation:
This is true because no chemical bonding or change was involved only mechanical mixing.
URGENT PLEASE ELPP!!!Calculate the density of a piece of metal that has a mass of 2.5 × 102 kg and a volume of 4.1 × 103 m3.
Answer:
Density =mass/Volume
First of all let's find the mass
= 2.5 ×102kg
= 225kg
Then the volume
=4.1 × 103 m3
=422.3m3
225kg /422.3m3
=0.53279659
The density of a piece of metal that has a mass of 2.5 × 102 kg and a volume of 4.1 × 103 m3 will be 6.03 kg/m³ .
What do you mean by the density of a substance ?
Density is defined as the ratio of mass of the object to the volume of the object. Different substances have different densities.
The mathematical expression for density is as follows:
Density=Mass/Volume
The mass of a substance is expressed in kilograms and the volume is expressed in liter.
Thus, the unit of density is kg L⁻¹.
The density of a substance does not depend on the amount of the matter.
Thus, density is an intensive property.
To calculate the density -:
Given,
Mass= 2.5 ×102 kg=2550 kg
Volume=4.1 × 103 m³=422.3m³
Density=mass/volume
Density=2550/422.3
Density=6.03kg/m³
Hence, 6.03kg/m³ is the density of a piece of metal .
Learn more about density ,here:
https://brainly.com/question/15164682
#SPJ5
What is the temperature of 0.5 moles of water vapor that occupies 120 dm3 and applies a pressure of 15,000 Pa to its container?
A. 433.21 K
B. 5.19 K
C. 7.52 K
D. 108.3 K
Reset Selection
Answer:
The answer is C. 7.52 K
Explanation:
hope it helps
Which feature forms at Earth's surface from the cooling of lava?
O extrusion
fault
O intrusion
unconformity
Extrusion is the feature form at Earth's surface from the cooling of lava.
What are extrusive igneous rocks?They are the ones that originate from a sudden cooling of the incandescent magma when it comes to the surface, which means that there is no time for crystals to form, either partially or totally.
Characteristics of extrusive igneous rocksThese are rocks formed mainly by silicate minerals.Pyroclastics are the product of explosive volcanic eruptions and contain rock fragments of different origins, they can be of many shapes and sizes.Therefore, we can conclude that typical volcanic rocks are formed by the rapid cooling of lava and pyroclastic fragments.
Learn more about extrusive igneous rocks here: https://brainly.com/question/1340933
Answer:
A.
Explanation:
the first attempt to classify the elements was made by newlands true or false
Answer:
True. An English scientist by the name of John Newlands tried to classify the elements in a unique manner. He first started by arranging all the elements in a ascending order according to their atomic weights.
45. The following data was collected for 3 compounds:
Mass of Nitrogen that combines with 1 g of Oxygen
Compound A 1.750 g
Compound B 0.8750 g
Compound C 0.4375 g
Show whether these are the same or different compounds. What chemical law is being observed here?
Answer:
The three compounds are different compounds
Explanation:
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound A = 1.750 g
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound B = 0.8750 g
The mass of Nitrogen that combines with 1 gram of Oxygen in Compound C = 0.4375 g
According to the law of multiple proportions, when atoms of two different elements react to form compounds, the masses of one of the elements that combines with a fixed mass of the other element are in small whole number ratios.
The ratio of the masses are;
Mass of Nitrogen in Compound B/(Mass of Nitrogen in Compound C = 0.8750/0.4375 = 2
Mass of Nitrogen in Compound A/(Mass of Nitrogen in Compound C = 1.750/0.4375= 4
Mass of Nitrogen in Compound A/(Mass of Nitrogen in Compound B = 1.750/0.8750= 2
Given that the masses of Nitrogen in the three compounds are in small whole number ratios, the three compounds, Compound A, Compound B, and Compound C are different compounds.
What is the PRECAUTION for an Irritant?
A 1.30 L buffer solution consists of 0.107 M butanoic acid and 0.345 M sodium butanoate. Calculate the pH of the solution following the addition of 0.075 moles of NaOH . Assume that any contribution of the NaOH to the volume of the solution is negligible. The Ka of butanoic acid is 1.52×10−5 .
Answer:
The pH of the solution following the addition of 0.075 moles of NaOH is 5.7.
Explanation:
The equation of the buffer solution is the following:
C₄H₇O₂H(aq) + H₂O(l) ⇄ C₄H₇O₂⁻(aq) + H₃O⁺(aq) (1)
The pH of the buffer solution can be found using the Henderson-Hasselbalch equation:
[tex] pH = pKa + log(\frac{[NaC_{4}H_{7}O_{2}]}{[C_{4}H_{8}O_{2}]}) [/tex] (2)
The NaOH added will react with butanoic acid tot produce sodium butanoate:
C₄H₇O₂H(aq) + OH⁻(aq) ⇄ C₄H₇O₂⁻(aq) + H₂O(l) (3)
[tex] n_{C_{4}H_{7}O_{2}H}_{i} = C*V = 0.107 M*1.30 L = 0.139 moles [/tex]
[tex] n_{C_{4}H_{7}O_{2}^{-}} = 0.345 M*1.30 L = 0.449 moles [/tex]
[tex] n_{NaOH} = 0.075 moles [/tex]
[tex] n_{C_{4}H_{7}O_{2}H} = 0.139 moles - 0.075 moles = 0.064 moles [/tex]
[tex] n_{C_{4}H_{7}O_{2}^{-}} = 0.449 moles + 0.075 moles = 0.524 moles [/tex]
[tex]C_{C_{4}H_{7}O_{2}H} = \frac{0.064 moles}{1.30 L} = 0.049 M[/tex]
[tex] C_{C_{4}H_{7}O_{2}^{-}} = \frac{0.524 moles}{1.30 L} = 0.403 M [/tex]
Now, from equation (1) we have:
C₄H₇O₂H(aq) + H₂O(l) ⇄ C₄H₇O₂⁻(aq) + H₃O⁺(aq)
0.049 - x 0.403 + x x
[tex] Ka = \frac{[C_{4}H_{7}O_{2}^{-}][H_{3}O^{+}]}{C_{4}H_{7}O_{2}H} [/tex]
[tex]1.52 \cdot 10^{-5} = \frac{(0.403 + x)x}{0.049 - x}[/tex]
[tex]1.52 \cdot 10^{-5}*(0.049 - x) - (0.403 + x)x = 0[/tex]
By solving the above equation for x we have:
x = 1.85x10⁻⁶ = [H₃O⁺]
So, the concentration of butanoic acid and sodium butanoate is:
[tex][C_{4}H_{7}O_{2}^{-}] = 0.345 + 1.85 \cdot 10^{-6} = 0.345 M[/tex]
[tex][C_{4}H_{7}O_{2}H] = 0.049 - 1.85 \cdot 10^{-6} = 0.049 M[/tex]
Finally, from equation (2) we have:
[tex] pH = pKa + log(\frac{[NaC_{4}H_{7}O_{2}]}{[C_{4}H_{8}O_{2}]}) [/tex]
[tex]pH = -log(1.52 \cdot 10^{-5}) + log(\frac{0.345}{0.049}) = 5.7[/tex]
Therefore, the pH of the solution following the addition of 0.075 moles of NaOH is 5.7.
I hope it helps you!
P= f/a solve it for f
Answer:
Force = Pressure × Area
Explanation:
Easy, just invert the equation. Transpose the force variable over to the left of the equals sign, and transpose the pressure variable back to the right side.
SOMEONE PLEASE HELP HURRY
I think the answer is A. I know it's Planet X.
can someone send me something to get chemistry going ;);)
Answer:
Check out libretexts chemistry
Explanation:
It's basically an online free textbook for lots of subjects
highly recommended
Ok , whenever you wanna study chemistry , listen to music that you love. So each time you have to study chem , you will be excited bc u also wanna hear that music u love. Similarly , for every boring work you do , reward yourself for it. It helps , Im sure.
Thank you XD
which statement best describes a mole? it is 12 units of a given substance. it contains 6.02 1023 grams of sodium chloride. it is the mass of 12 carbon atoms. it contains 6.02 1023 particles of a given substance.
Answer:
The correct option is;
It contains 6.02 × 10²³ particles of a given substance
Explanation:
A mole of substance is the standard scientific unit of measurement for the quantity of the substance which is made up of a large number of small particles such as molecules, ions, atoms, electrons or other entities.
The General Conference on Weights and Measures defines the mole as the amount of a substance that contains 6.02214076 × 10²³ units of entities
The number 6.02214076 × 10²³, is also known as Avogadro's number.
The statement which correctly describes the mole is; it contains 6.02 × 10^23 particles of a given substance.
The mole refers to the amount of substance that contains the same number of elementary entities as 12 g of carbon - 12. According to Avogadro's law, the number of elementary entities in a substance is 6.02 × 10^23. These elementary entities could be atoms, ions, molecules etc.
Therefore, the statement which correctly describes the mole is; it contains 6.02 × 10^23 particles of a given substance.
Learn more: https://brainly.com/question/12108425
What u learned about the states of matter?
Answer:t
Explanation:
In everyday life, four states of matter are visible: solid, liquid, gas, and plasma.
Of course, matter also has other states, such as Bose-Einstein density and Fermion density, but these states are only observed under certain conditions.
A pharmaceutical company is making a large volume of nitrous oxide (NO). They predict they will be able to make a maximum amount of 4860 grams with the materials they have in stock. From the previous 10 volumes they have made, they know that the percent yield of this reaction is fairly low at 47%. How much will the actual yield be? A. 228 grams B. 2284 grams C. 10340 grams D. 486 grams
Answer:
The answer is "Option B"
Explanation:
From the query, the following knowledge is derived:
Yield in percentage = 47%
Performance of theory = 4860 g
Actual yield Rate =?
The percentage return is defined simply by the ratio between both the real return as well as the conceptual return multiplied by the 100. It's also represented as numerically:
[tex]Rate = \frac{Existing \ Rate} {Theoretical \ Rate} \times 100[/tex]
Now We can obtain the percent yield as followed using the above formula:
[tex]\text{Yield in percentage}= \frac{Actual \ yield \ Rate} {Theorical \ Rate} \times 100[/tex]
[tex]47\% = \frac{Actual \ yield \ Rate}{4860}[/tex]
The value of the Actual yield Rate =[tex]47\% \times 4860[/tex]
[tex]= \frac{47}{100} \times 4860 \\\\ = 2284.2 g[/tex]
The Actual yield Rate= 2284.2 g.
Environmental scientists are unconcerned with methods to preserve natural resources.
Please select the best answer from the choices provided
T
F
Answer:
False
Explanation:
b. What chemist finds
out how much nitrogen is in a sample of air
A chemical equation is balanced when Group of answer choices the number of atoms of each element is the same in reactants and products. the charge on each atom is the same in reactants and products. the sum of the coefficients of the reactants is equal to the sum of the coefficients of the products. the total number of ions is the same in reactants and products. the total number of molecules is the same in reactants and products.
Answer:
a
Explanation:
A chemical equation is said to balanced only when the number of atoms of each element is the same in both reactants and products side. Rest all options are absurd. Hence, option a is correct.
Balancing of the reaction has no relation with coefficient, molecules or charge of the elements
Identify an element as a metal or a non-metal according to its position in the Periodic
Table
Answer:
Metals on the left of the Periodic Table.
Non-Metals on the top-right, plus Hydrogen.
what is organic chemistry
Answer:
Organic chemistry
Explanation:
Organic chemistry is part of the chemistry that studies carbon compounds, which also use organic compounds, which have characteristics.
Which statement about Schrödinger’s theory of the atomic model is true?
Answer:
it explain odds of finding the position of an electron.
Need help :)….please
Answer:
i think B is correct
Explanation:
A star is estimated to have a mass of 2.0 x 10 ^36kg. Assuming it to be a sphere of average radius of 7.0 x 10 ^5 km. Calculate the average density of the star in g/cm^3 and in lb/ft^3
Answer:
a) 1.392 x 10^6 g/cm^3
b) 8.69 x 10^7 lb/ft^3
Explanation:
mass of the star m = 2.0 x 10^36 kg
radius of the star (assumed to be spherical) r = 7.0 x 10^5 km = 7.0 x 10^8 m
The density of substance ρ = mass/volume
The volume of the star = volume of a sphere = [tex]\frac{4}{3}\pi r^{3}[/tex]
==> V = [tex]\frac{4}{3}*3.142*(7.0*10^8)^{3}[/tex] = 1.437 x 10^27 m^3
density of the star ρ = (2.0 x 10^36)/(1.437 x 10^27) = 1.392 x 10^9 kg/m^3
in g/cm^3 = (1.392 x 10^9)/1000 = 1.392 x 10^6 g/cm^3
in lb/ft^3 = (1.392 x 10^9)/16.018 = 8.69 x 10^7 lb/ft^3
Doing my summer school work right now. Please help me pass I don’t want to take chemistry for the third time.
Answer:
13.B 0.15 M KBr
14.C 1 M C²h⁵OH
15.D 0.1 M C⁶H¹²o⁶
16.A 2 K² SO⁴
17.A 2 M K² SO⁴
18.D 0.028 M KBr
19.A 1 M Nal
20.B 0.1 M AICI³
156. A solid metal sphere has a volume of 4.2 ft}. The mass
of the sphere is 155 lb. Find the density of the metal
sphere in grams per cubic centimeter.
Answer:
The answer is
0.59 g/cm³Explanation:
To find the density of the sphere we use the formula
[tex]Density \: = \frac{mass}{volume} [/tex]To find the density in g/cm³ first convert the mass into grams and the volume into cm³
For the mass we have
155 lb = 70306.82 g
For the volume
4.2 ft³ = 118930.76 cm³
Substitute the values into the above formula
That's
[tex]Density \: = \frac{70306.82 \: g}{118930.76 \: cm³} [/tex]We have the final answer as
Density = 0.59 g/cm³Hope this helps you
According to the table, a 23-30 watt CFL provides __________ lumens and is equivalent to a ________ incandescent bulb.
Answer:
The correct options are;
1. 1,600
2. 100 Watts
A 23-30 watt CFL provides 1,600 lumens and is equivalent to a 100 Watts incandescent bulb
Explanation:
Brightness is measured in lumens and watts measure energy usage therefore with the use of an energy saving light bulb, the same lumination can be obtained at a lower energy usage.
According to a comparison chart for LED Lights vs. Incandescent Light Bulbs vs. Compact Fluorescents (CFLs) from USAI lightening website 23-30 watts CFL has a light output of 1,600 and is therefore produces enough light as a 100 Watts Incandescent Light Bulb
Also according to energy.gov website, CFLs save up to 75% energy such that a 23-30 watt CFL can produce the same illumination as a 100 watt incandescent bulb
Therefore we have, a 23-30 watt CFL provides 1,600 lumens and is equivalent to a 100 Watts incandescent bulb.
Answer:
1600 lumens, 100 watt incandescent
Explanation:
100% on edge (:
In the molecule 4H2O2 the number of hydrogen atoms is what
Answer:
Scientists
Explanation:
Scientists because they are the one who makes hypothesis.