Explanation:
1.Graphite has a very high melting point because its structure consists of carbon atoms which are held together by strong covalent bonds
2.It has delocalised electrons.
(PLEASE HELP, LAST QUESTION I NEED! ) Describe to me the purpose of stoichiometry calculations.
Explanation:
Stoichiometry measures these quantitative relationships, and is used to determine the amount of products and reactants that are produced or needed in a given reaction. Describing the quantitative relationships among substances as they participate in chemical reactions is known as reaction stoichiometry.
Modern atomic theory states that atoms are neutral. How is this neutrality achieved? (3 points) Select one: a. Equal number of neutrons and protons b. Equal number of protons and electrons c. More electrons than protons d. More neutrons than electrons
Answer:
The answer is option B.
Equal number of protons and electronsHope this helps you
Answer:
equal number of electrons and protons
Explanation:
electron is negatively charged and proton is positively charged for an atom to stay neutrality # of electrons and protons must be equal.
A drug problem can quickly consume A)a small portions of a person income B)the bulk of a person income C)a person excess income
Answer:
b
Explanation:
a drug problem consumes the bulk of a persons income because drugs are expensive to buy
A drug problem can quickly consume the bulk of a person income
What is a drug problem?A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drug abuse or substance abuse refers to the use of certain chemicals for the purpose of creating pleasurable effects on the brain.
Drug use can have significant and damaging short-term and long-term effects. Taking some drugs can be particularly risky, especially if you take high doses or combine them with other drugs or alcohol.
People of any age, sex or economic status can become addicted to a drug. Certain factors can affect the likelihood and speed of developing an addiction.
The best way to prevent an addiction to a drug is not to take the drug at all. If your doctor prescribes a drug with the potential for addiction, use care when taking the drug and follow the instructions provided by your doctor. Thus you can save your income.
The correct answer is option B.
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The proof that ch4 is a weak acid
Answer: because ch4 is not considered a acid they said it is too weak
Explanation:
hurry I'm on a timer
Which term describes erosion?
O creates small particles
O hardens rock fragments
O transports solid materials
O dissolves rock components
Answer:
transports solid materials
Explanation:
Erosion is a process where solid materials are transported by natural forces such as wind or water.
Answer: c
Explanation:
How do mass and type of material affect thermal energy transfer?
Answer:
Temperature, mass, and the type of material are factors that affect the thermal energy of an object.
Material with the higher specific heat will have more thermal energy than material with lower specific heat if they both have the same mass and temperature.
The thermal energy within the thing increases if the temperature remains constant but the object's mass rises.
If two materials have the same mass and temperature, the material with the greater specific heat will have more thermal energy than the material with the lower specific heat.
How does thermal energy transfer depend on the kind of material?
The speed at which thermal energy moves from one end of a substance to another determines thermal conductivity. Insulators transport thermal energy slowly while conductors transfer thermal energy quickly.
The thermal energy within the thing increases if the temperature remains constant but the object's mass rises.
Conduction, convection, or radiation are all ways that thermal energy can be moved from one location to another.
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PLZ HELP SUPER STUCK T^T *will give brainiest* (30 points) (plz hurry!! its on a test)
Question: Aluminum is an element. Which best describes what makes up a sample of aluminum? one kind of atom two different kinds of atoms all carbon-based atoms a carbon atom and non-carbon atoms
Answer:
The answer to this is A. One kind of atom
Explanation:
The other options make no sense whatsoever. But enjoy.
I hope this helped.
Answer:
A. One kind of atom
Explanation:
What is the activation energy for the reaction in this energy diagram?
Answer:
+ 100 Kj
Explanation:
The very minimum energy required to activate atoms or molecules to undergo chemical transformation.
Answer:
It is 60kj.
Explanation:
It is the highest point minus where a+b is at, so it is 60kj.
4.Acrylic fibres are also known as
a)Terry cot
b)Orlon
c)Polyester
d)None of these
Answer:
B
Explanation:
DuPont created the first acrylic fibers in 1941 and trademarked them under the name Orlon.
What was the purpose of the periodic table?
A. To organize elements as they were discovered
O B. To list the chemical reactions an element can have
O C. To name elements as they were discovered
O D. To identify all the isotopes of each element
SUBMIT
Answer:
A
Explanation:
The purpose of the periodic table was to organize elements as they were discovered into periods and groups, according to their properties. It was not just a naming of elements, as a list.
The purpose of the periodic table was to organize elements as they were discovered. Thus option A is correct.
What is periodic table?Periodic table is defined as an arrangement of all known elements in order of increasing atomic number and recurrent chemical attributes.
It can also be defined as a tabular arrangement of chemical elements ordered by increasing atomic number and element groups.
It helps us to learn about an ordered grouping of the 118 known chemical elements.
The periodic table contains alkali metal, alkaline earth metal, transition elements, noble gas, post transition element etc. and many more elements are arranged in periodic table in groups.
Thus, the purpose of the periodic table was to organize elements as they were discovered. Thus option A is correct.
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Name one way chemicals can help the environment
Energy storage and transport. Chemical energy transport.
Answer:
to clean the water
Explanation:
How much energy does a 185 nm wave of light have? (The speed of light in a
vacuum is 3.00 x 108 m/s, and Planck's constant is 6.626 x 10-34 Jos.)
A. 1.07 x 10-18 J
B. 8.38 x 1034j
C. 9.31 x 1017 J
D. 3.68 x 10-32 J
O
Answer: A. 1.07 x 10∧ -18 J
Explanation:
The energy can be calculated by using this relation; E = hc / ∧
Where E = energy
h = Planck's constant = 6.626 x 10-34joules
c = speed of light = 3.00 x 10∧8 m/s
∧ = wavelenght = 185 nm = 185 x 10∧ -9m
Therefore; E= hc / ∧
= (6.626 x 10-34 j/s) x ( 3.00 x 10∧8 m/s) / 185 x 10∧ -9m
= 1.987 x 10 ∧ -25 / 185 x 10∧ -9m
= 1.07 x 10∧ -18 J
How are the properties of metals and non-metals different?
Answer:
Explanation:
Properties of metals:
1. They have a lustre ( shine )
2. They have a silvery-grey or golden-yellow colour.
3. They conduct heat and electricity.
4. They are ductile ( can be drawn into wires ) .
5.They are malleable ( can be hammered into thin sheets ).
6. They are sonorous ( make a ringing sound when hit ).
Properties of non-metals:
1. They display a variety of colours.
2. They are poor conductors of heat and electricity.
3. They are not lustrous, ductile or malleable.
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How do you find the amount of electrons for any element?
Answer:
If you know the number of protons and neutrons you have to simply subtract the number of neutrons by number of protons the answer will be number of neutron
Explanation:
Answer:
We can find the amount of electrons through its Atomic number and with the help of electronic configuration
How to calculate this ?
Do you use the molar mass and multiply it by the mass given ?
Answer:
Option C. 8.91g
Explanation:
The balanced equation for the reaction is given below:
2Pb(NO3)2 —> 2PbO + 4NO2 + O2
Next, we shall determine the mass of Pb(NO3)2 that decomposed and the mass PbO produced from the balanced equation.
This is illustrated below below:
Molar mass of Pb(NO3)2 = 207 + 2[14 + (16x3)]
= 207 + 2[14 + 48]
= 207 + 2[62] = 207 + 124
= 331g/mol
Mass of Pb(NO3)2 from the balanced equation = 2 x 331 = 662g
Molar mass of PbO = 207 + 16 = 223g/mol
Mass of PbO from the balanced equation = 2 x 223 = 446g
Summary:
From the balanced equation above,
662g of Pb(NO3)2 decomposed to produce 446g of PbO.
Finally, we can obtain the maximum mass of lead(II) oxide, PbO produced from 13.23g of lead (II) nitrate, Pb(NO3)2 as follow:
From the balanced equation above,
662g of Pb(NO3)2 decomposed to produce 446g of PbO.
Therefore, 13.23g of Pb(NO3)2 will decompose to produce = (13.23 x 446)/662 = 8.91g of PbO.
Therefore, 8.91g of PbO were obtained from the decomposition of 13.23g of Pb(NO3)2
what's love like? what feels are involved?
if 140cm3 of methane diffuse into air in 72 sec,how long will it take 210cm3 of sulphur dioxide to diffuse under the same condition ?
Answer:
time for sulphur dioxide to diffuse is 221.05 secs
The time for sulphur dioxide to diffuse is 108 sec.
Which gas diffuses twice quickly as SO2?Sulfur dioxide has a molecular weight of sixty-four and as a result, the square root is 8. since its inversely proportional, on the way to diffuse two times as fast, the rectangular root of the molecular weight should be 4, and subsequently the molecular weight might be 16. So the solution is methane (CH4).
Which gases diffuse the fastest?The charge of diffusion for a gas is inversely proportional to the rectangular root of its molecular mass (Graham's law). The gasoline with the lowest molecular weight will effuse the fastest. The lightest, and consequently fastest, fuel is helium.
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Need help ASAP!!!! what is the value (angle) for the C=C=O bond in Ketene i.e. CH2=C=O
Answer:
[tex]180^\circ[/tex] by the VSEPR theory.
Explanation:
This question is asking for the bond angle of the [tex]\rm C=C=O[/tex] bond in [tex]\rm H_2C=C=O[/tex]. The VSEPR (valence shell electron pair repulsion) theory could help. Start by considering: how many electron domains are there on the carbon atom between these two bond?
Note that "electron domains" refer to covalent bonds and lone pairs collectively.
Each nonbonding pair (lone pair) of valence electrons counts as one electron domain.Each covalent bond (single bond, double bond, or triple bond) counts as exactly one electron domain.For example, in [tex]\rm H_2C=C=O[/tex], the carbon atom at the center of that [tex]\rm C=C=O[/tex] bond has two electron domains:
This carbon atom has two double bonds: one [tex]\rm C=C[/tex] bond and one [tex]\rm C=O[/tex] bond. Even though these are both double bonds, in VSEPR theory, each of them count only as one electron domain. Keep in mind that there are only four valence electrons in each carbon atom. It can be shown that all four valence electrons of this carbon atom are involved in bonding (two in each of the two double bonds.) Hence, there would be no nonbonding pair around this atom.In VSEPR theory, electron domains around an atom repel each other. As a result, they would spread out (in three dimensions) as far away from each other as possible. When there are only two electron domains around an atom, the two electron domains would form a straight line- with one domain on each side of the central atom. (To visualize, consider the three atoms in this [tex]\rm C=C=O[/tex] bond as three spheres on a stick. The central [tex]\rm C[/tex] atom would be between the other [tex]\rm C[/tex] atom and the [tex]\rm O[/tex] atom.)
This linear geometry corresponds to a bond angle of [tex]180^\circ[/tex].
in Analytical chemistry laboratory. Nickle(ppm)in water sample estimated by two different students was as ,student 1 (25 24 24 24 24 28 26 ) and student 2 (24 25 24 24 25 25 ), if the true valude on Nickle in water was 20 ppm estimate the precision and accuracy of both students
Answer:
Answers are in the explanation
Explanation:
Precision and accuracy are both statistical concepts. Precision is about how close are the measured values to each other. Accuracy is closeness of the measured values to a specific value or reference value.
There are many ways to calculate precision and accuracy, one is stimating precision as Relative Uncertainty and accuracy as Relative Error.
Formulas are:
Relative Uncertainty: Standard desviation / Measured value.
Relative Error: Measured Value - Expected Value / Expected value
Measured value is the aveage of the values.
For student 1:
Mean = 25
Standard desviation = 1.5275
Relative Uncertainty: 1.5275 / 25
Relative Uncertainty: 0.061
Relative Error: 25 - 20 / 20
Relative Error: 0.25
For student 2:
Mean = 24.5
Standard desviation = 0.5477
Relative Uncertainty: 0.5477 / 24.5
Relative Uncertainty: 0.02
Relative Error: 24.5 - 20 / 20
Relative Error: 0.225
As the student 2 has a low Relative error and uncertainty, you can say student 2 is more accurate and precise
Hi does anyone know how to do question 4?
Please show working out thanks.
answer:
a)1.274 g b) 0.013 mole
Explanation:
a) Mass of 1 mol of CuSo4. 5H20=
[tex]63 + 32 + (16 \times 4) + (7 \times 1) + (16 \times 5)[/tex]
=246g
no. moles of CuSo4. 5H2O=
[tex] \frac{mass}{mass \: of \: 1mole} [/tex]
so moles
=
[tex] \frac{3.14}{246} [/tex]
0.013 mole
in the equation
1 mole of sulphuric acid reacts to form 1 mole of CuSo4.5H2O
in other words
0.013 mole of sulphuric acid reacts to form 0.013 mole of CuSo4.5H2O
so mass of 1 mole (Mr) H2So4=
[tex](2 \times 1) + 32 + (16 \times 4)[/tex]
98g
mass of sulphuric acid= mole × mass of 1 mole
so mass= 0.013 × 98
1.274 g
b) In the equation
1 mole of sulphuric acid reacts to form 1 mole of copper(ll) oxide
in other words
0.013 mole of sulphuric acid reacts to form 0.013 mole of copper (ll) oxide
so 0.013 mole of copper(ll) oxide is reacted
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first ionization energy
Answer:
The first ionization energy is defined as
Energy which is required to pull out one mole of the outermost shell's electrons in a neutral atom from one mole of gaseous atoms to produce 1 mole of gaseous ions each with a charge of 1+.[tex]A\to A^++ e^{-}[/tex] , where A is any neutral atom.In the periodic table, Its value decreases from top to bottom in groups and increases from left to right across a particular period. Helium has the largest first ionization energy.Francium has one of the lowest.Which of the following is a characteristic property of the halogen? A. They are very reactive B. They are very stable C. They are metals D. They are all gases
Answer:A
Explanation:
They are very reactive is a characteristic property of halogen.
Hence, Option (A) is correct answer.
What is Halogen ?Halogens are non metallic elements in periodic table. It belongs to group 17 in the periodic table. Halogen family consists six elements that is Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), Astatine (At) and Tennessine (Ts).
What are the characteristics property of halogen ?They are nonmetals. Halogens have 7 valence electrons. They are highly reactive with alkaline earth metal and alkali metals. Halogens are not stable.Thus, from the above conclusion we can say that They are very reactive is a characteristic property of halogen.
Hence, Option (A) is correct answer.
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Which will change will cause the gravitational force between a baseball and a soccerball
is a process that involves the collection of information and ideas supported by evidence.
Science
Systematics
Pseudoscience
Hypothesis
Answer:
pseudoscience
Explanation:
srry that this is so late btw, hope this helps...
Answer:
Science
Explanation:
First response is NOT correct
Select the most dilute solution a.A solution made by dissolving 60g of sodium hydroxide in 2000cm cubed b.A solution made by dissolving 40 g of sodium hydroxide in 1000 cm cubed of solution. c.A solution made by dissolving 10 g of sodium hydroxide in 250 cm cubed of solution. d.A solution made by dissolving 20 g of sodium hydroxide in 500 cm3 of solution.
Answer:
A, a solution made by dissolving 60g of sodium hydroxide in 2000cm³
Explanation:
Concentration = no. of moles / volume (in dm³)
1 dm³ = 1000cm³
no. of moles = mass / molar mass
molar mass of NaOH = 23.0+16.0+1.0 = 40 g/mol
Let's find the concentration of each of the solutions:
A:
= 60/40 /2
= 0.75 mol/dm³
B:
= 40/40 /1
= 1 mol/dm³
C:
= 10/40 / 0.25
=1 mol/dm³
D:
= 20/40 / 0.5
= 1 mol/dm³
Since 0.75mol/dm³ is the lowest concentration out of 4, it is the most dilute.
Determine the net iconic equation for the following chemical reaction: HCl(aq) + NH4OH(aq)———-> NH4Cl(aq) + H2O(I) Hint: HCl(aq) is strong acid NH4OH(aq) is a weak base
Answer : The net ionic equation will be,
[tex]H^{+}(aq)+OH^{-}(aq)\rightarrow H_2O(l)[/tex]
Explanation :
In the net ionic equations, we are not include the spectator ions in the equations.
Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.
The given balanced ionic equation will be,
[tex]HCl(aq)+NH_4OH(aq)\rightarrow NH_4Cl(aq)+H_2O(l)[/tex]
The ionic equation in separated aqueous solution will be,
[tex]H^+(aq)+Cl^-(aq)+NH_4^+(aq)+OH^-(aq)\rightarrow H_2O(l)+NH_4^+(aq)+Cl^-(aq)[/tex]
In this equation, [tex]NH_4^+\text{ and }Cl^-[/tex] are the spectator ions.
By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.
The net ionic equation will be,
[tex]H^{+}(aq)+OH^{-}(aq)\rightarrow H_2O(l)[/tex]
When a sample of Mg is combusted in a bomb calorimeter, 25.4 kJ of energy as heat is evolved. The calorimeter contains 7.50 x 102 g of water at an initial temperature of 18.6 °C. The specific heat capacity of water is 4.184 J/gLaTeX: \cdot⋅°C and the heat capacity of the bomb is 8.20 x 102 J/°C. Calculate the final temperature of the water and the bomb
Answer:
x = 25.02 or 25°c
Explanation:
Given:
mass of water : 7.50×10² =750 gm
Ccal = 8.20× 10² = 820 J/°c
Let assume final temp = x°c
then, heat gained by the water + heat gained by calorimeter
= 25400 J
⇒ Mw × Cw× ΔTw+ Ccal ×ΔT = 25400
⇒ 750× 4.184 × (x - 18.6) + 820 ×(x-18.6) = 25400
⇒ x = 25.02 or 25°c
Acid rain is the direct result of acid released by burning fossil fuels.
Please select the best answer from the choices provided
ОТ
OF
Answer:
The answer is TrueHope this helps you
I need a help from this question!!
Answer:
B
Explanation:
Please take a look at the picture attached for the drawings and structures.
C2H4 is a alkene (C-C double bond). When steam (water) is added, it turns into an alcohol, where the double bond breaks and a (-OH) functional group is attached to one of the Carbons. In this case, C2H4 ethene is turned into ethanol.
When an alcohol undergoes oxidation, primary alcohols turn into aldehyde (-CHO) or carboxylic acids (-COOH). Secondary alcohol turns into ketone. Ethanol is a primary alcohol. And since it later reacts with propanol, it can only form carboxylic acid when it oxidizes. The product in this reaction is ethanoic acid.
Carboxylic acid reacts with alcohol to form an ester (-COO-). the -COOH group from acid combines with the -OH group from alcohol to form an ester bond -COO- while eliminating H2O. Therefore, when propanol undergoes esterification with ethanoic acid, propyl ethanoate is produced. It is the answer of B.
Consider the equation below.
Zn + H2SO4 → ZnSO4 + H2
The mole ratio of zinc to zinc sulfate is
Answer:
1:1
Explanation:
There is one mole of zinc (Zn) and one mole of zinc sulfate (ZnSO₄).
The mole ratio is 1:1.
Hope this helps.
Answer:
1:1
Explanation: