Answer:
See explanation
Explanation:
In Bohr's theory, electrons are found in specific regions in space called orbits. These orbits are also called energy levels. An electron may move from one energy level to another by absorbing or emitting energy.
In the wave mechanical model, electrons are not found in a particular region in space according to Heisenberg's uncertainty principle.
We rather define a certain region in space where there is a high probability of locating the electron. This region in space where there is a high probability of locating the electron is called an orbital.
Hence, in the Bohr's model of the atom,electrons can surely be found in orbits while in the wave mechanical model, the orbital is a probability function that describes a region in space where an electron may be found.
What is the frequency of an electromagnetic wave with a wavelength of 1.0 x 10' m?
a. 3.3 x 104 Hz
1.0 x 101 Hz
b. 3.0 x 10 Hz
d. 3.0 x 103 Hz
c.3.0 x 103 Hz
Methane is approximately 23 times more powerful than carbon dioxide as a greenhouse gas. Which are significant sources of methane emissions
Answer:
anthropogenic sources like landfills, agricultural activities,coal mining and combustion and some sources are natural ones
What are the uses of iron and it's reasons.
Answer:
Uses of iron
It is used to manufacture steel and also used in civil engineering like reinforced concrete, girders etc. Iron is used to make alloy steels like carbon steels with additives such as nickel, chromium, vanadium, tungsten, and manganese.
Answer:
iron is used to make water pipes.
used for making machines in industries.
used for making steam engine.
Calculate the molecular weight of a dibasic acid.0.56gm of which is required 250ml of N/20 sodium hydroxide solution for neutralization.
Answer: The molecular weight of the dibasic acid is 89.6 g/mol
Explanation:
Normality is defined as the amount of solute expressed in the number of gram equivalents present per liter of solution. The units of normality are eq/L. The formula used to calculate normality:
[tex]\text{Normality}=\frac{\text{Given mass of solute}\times 1000}{\text{Equivalent mass of solute}\times \text{Volume of solution (mL)}}[/tex] ....(1)
We are given:
Normality of solution = [tex]\frac{1}{20}=0.05N[/tex]
Given mass of solute = 0.56 g
Volume of solution = 250 mL
Putting values in equation 1, we get:
[tex]0.05=\frac{0.56\times 1000}{\text{Equivalent mass of solute}\times 250}\\\\\text{Equivalent mass of solute}=\frac{0.56\times 1000}{0.05\times 250}=44.8g/eq[/tex]
Equivalent weight of an acid is calculated by using the equation:
[tex]\text{Equivalent weight}=\frac{\text{Molar mass}}{\text{Basicity}}[/tex] .....(2)
Equivalent weight of acid = 44.8 g/eq
Basicity of an acid = 2 eq/mol
Putting values in equation 2, we get:
[tex]44.8g/eq=\frac{\text{Molar mass}}{2eq/mol}\\\\\text{Molar mass}=(44.8g/eq\times 2eq/mol)=89.6g/mol[/tex]
Hence, the molecular weight of the dibasic acid is 89.6 g/mol
The field around a negatively charged object is symbolized by vectors pointing toward the sphere because a test charge, which is ______ by definition, would travel along such a vector if released in the field.
Positive
Negative
Answer:
Positive
Explanation:
what is the [h+] if the ph of a solution is 11.13
pls help
Explanation:
[tex][{H}^{ + }] = {10}^{ - pH} [/tex]
[tex] = {10}^{ - 11.13} [/tex]
[tex] = {10}^{ (- 11 - 0.13)} [/tex]
[tex] = {10}^{ - 0.13} \times {10}^{ - 11} [/tex]
[tex] = 0.741 \times {10}^{ - 11} \frac{mol}{litre} [/tex]
HOPE IT HELPS YOUIf charge on only one object is tripled, determine the new force between them:
Answer:
+3·F
Explanation:
The number of objects in the given system = 2 objects
The charge on each object are; q₁ = -Q, q₂ = -Q
The force acting between the objects = +F
The distance between the objects = 2·d
The formula for the force acting between two charged particles is given as follows;
[tex]F=K \times \dfrac{q_{1} \times q_{2}}{r^{2}}[/tex]
Therefore, we get;
[tex]F=K \times \dfrac{-Q \times -Q}{(2\cdot d)^{2}} = K \times \dfrac{Q^2}{4 \cdot d^2}[/tex]
By tripling the charge, q₁, on the first object, we get;
q₂ = 3 × (-Q)
[tex]F_2=K \times \dfrac{-3 \cdot Q \times -Q}{(2\cdot d)^{2}} = K \times \dfrac{3 \cdot Q^2}{4 \cdot d^2} = 3 \times +F = +3\cdot F[/tex]
Therefore, the new force between them, F₂ = +3·F
The weight of an object _____.
a) is always the same
b) depends on its location
c) is not affected by gravity
d) is the same as its mass
Answer:
c
Explanation:
and that's bc it will not share stay the same
Wood is made mostly of cellulose and has a chemical formula of C.H.00. Which of the following equations
represents the cellulose combustion reaction?
Answer:
Option B.
C₆H₁₀O₅ + 6O₂ —> 6CO₂ + 5H₂O
Explanation:
To know which option is correct, we shall write the balanced equation for the combustion of cellulose. This is illustrated below:
C₆H₁₀O₅ + O₂ —> CO₂ + H₂O
There are 6 atoms of C on the left side and 1 atom on the right side. It can be balance by writing 6 before CO₂ as shown below:
C₆H₁₀O₅ + O₂ —> 6CO₂ + H₂O
There are 10 atoms of H on the left side and 2 atoms on the right side. It can be balance by writing 5 before H₂O as shown below:
C₆H₁₀O₅ + O₂ —> 6CO₂ + 5H₂O
There are a total of 7 atoms of O on the left side and a total of 17 atoms on the right side. It can be balance by writing 6 before O₂ as shown below:
C₆H₁₀O₅ + 6O₂ —> 6CO₂ + 5H₂O
Now, the equation is balanced.
Thus, option B gives the correct answer to the question.
what is 10x412x3021x13123
The reaction below shows how the potential energy changes during a phase
change. What does the red arrow show?
Potential Energy
Reaction Progress
A. The change in enthalpy is positive, and the reaction is
endothermic.
B. The change in enthalpy is negative, and the reaction is exothermic.
C. The activation energy is negative, and the reaction is exothermic.
D. The activation energy is positive, and the reaction is endothermic.
Answer:
the red arrow shows that the change in enthalpy is positive
From the energy diagram, it is clear that, the enthalpy of the reaction is positive and it is an endothermic reaction.
What is an endothermic reaction ?An endothermic reaction is a chemical reaction that absorbs heat from its surroundings, resulting in a decrease in temperature of the surroundings. In other words, energy is taken in by the reaction from the environment.
During an endothermic reaction, the reactants absorb energy in the form of heat, light, or electricity to break the bonds between their atoms and form new bonds to create products.
The amount of energy absorbed by the reactants is greater than the energy released by the products. This energy difference is usually expressed as the enthalpy change (∆H) of the reaction, which is positive for endothermic reactions.
Here, the energy of products is higher than that of reactants and hence option A is correct.
Find more on endothermic reaction:
https://brainly.com/question/2264325
#SPJ7
Nitrogen dioxide gas is dark brown in color and remains in equilibrium with dinitrogen tetroxide gas, which is colorless.
2NO2(g) ⇌ N2O4(g)
When a light brown colored mixture of the two gases at equilibrium was moved from room temperature to a higher temperature, the mixture turned dark brown in color.
Which of the following conclusions about this equilibrium mixture is true?
This reaction is exothermic because the system shifted to the left on heating.
This reaction is exothermic because the system shifted to the right on heating.
This reaction is endothermic because the system shifted to the left on heating.
This reaction is endothermic because the system shifted to the right on heating.
Answer:
This reaction is exothermic because the system shifted to the left on heating.
Explanation:
2NO₂ (g) ⇌ N₂O₄(g)
Reactant => NO₂ (dark brown in color)
Product => N₂O₄ (colorless)
From the question given above, we were told that when the reaction at equilibrium was moved from room temperature to a higher temperature, the mixture turned dark brown in color.
This simply means that the reaction does not like heat. Hence the reaction is exothermic reaction.
Also, we can see that when the temperature was increased, the reaction turned dark brown in color indicating that the increase in the temperature favors the backward reaction (i.e the equilibrium shift to the left) as NO₂ which is the reactant is dark brown in color. This again indicates that the reaction is exothermic because an increase in the temperature of an exothermic reaction will shift the equilibrium position to the left.
Therefore, we can conclude that:
The reaction is exothermic because the system shifted to the left on heating.
The reaction is exothermic and the equilibrium position shifted to the left hand side.
An exothermic reaction is one in which heat is given out. Hence, the equilibrium position moves towards the left when the temperature is increased in an exothermic reaction.
Given the reaction, 2NO2(g) ⇌ N2O4(g) the appearance of a dark brown gas at high temperature implies that the reaction is exothermic and the equilibrium position shifted to the left hand side.
Learn more about exothermic reaction: https://brainly.com/question/15308590
What is the cause of acid precipitation?
1) ozone
2) nitrogenous oxides
3) ammonia
4) chlorofluorocarbons (CFCs)
Answer:
nitrogenous oxides
Explanation:
Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. ... In addition, the exhaust from cars, trucks, and buses releases nitrogen oxides and sulfur dioxide into the air. These pollutants cause acid rain.
The correct answer in you question is 2) nitrogenous oxide
I hope it helps ●~●
#CarryOnLearningA student distills a sample of ink. Devise a simple method to show that the liquid collected is pure water. Include the expected results in your answer.
Answer:
Distillation
Explanation:
Water vaporizes at lower temperature than the ink pigment so if you heat them, the water evaporates, leaving the ink pigment in the flask
Which of the following happens during an endothermic chemical change?
Heat is absorbed.
Heat is released.
Net energy decreases.
Net energy remains constant.
Answer:
Heat is absorbed.
Explanation:
Endothermic reactions: Heat is absorbed.
When there is a change in the endothermic chemical so here heat is absorbed.
What are Endothermic reactions?It is the type of the chemical reaction that absorbed the heat from the environment. The absorbed energy that gives the activation energy for the reaction to arise.
hence, When there is a change in the endothermic chemical so here heat is absorbed.
Therefore, the first option is correct.
Learn more about heat here: https://brainly.com/question/1488118
what are condition for formation of electrovalent bond
Answer:
The conditions for the formation of an electrovalent bond are as follows: The atom which changes into cation (+ ive ion) should possess 1,2 or 3 valency electrons. It will loose these electrons to form cation with +1,+2 or +3 charge
A balloon, inflated in an air-conditioned room at 27.0°C, has a volume
of 4.50.L. It is heated to a temperature of 57.0°C. What is the new
volume of the balloon if the pressure remains constant?
Answer:
4.95L
Explanation:
Using Charle's law equation;
V1/T1 = V2/T2
Where;
V1 = initial volume (L)
V2 = final volume (L)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the question, the following information was given:
V1 = 4.50L
V2 = ?
T1 = 27°C = 27 + 273 = 300K
T2 = 57°C = 57 + 273 = 330K
Using V1/T1 = V2/T2
4.50/300 = V2/330
Cross multiply
300 × V2 = 4.5 × 330
300V2 = 1485
V2 = 1485 ÷ 300
V2 = 4.95L
air is made up of different gasses such as oxygen nitrogen and carbon dioxide. which statement best describes these three components of air?
-they are all classified as pure substances
-they cannot react with another substance
-they are chemically bonded to one another
-they can be classified as elements
Answer:
They are chemically bonded to one another
Answer:
they can be classified as elements
Balance the equation
__Cu+__Ag(NO3)——__Cu(NO3)2+__Ag
Balanced chemical equation for above reaction :
[tex] \mathrm{Cu +2 \: AgNO_3 \longrightarrow Cu(NO_3)_2 + 2 \: Ag}[/tex]
This is a displacement reaction, where copper (Cu) being morereactive than Silver (Ag) displaces Silver from its compound " Silver Nitrate " to form " Copper Nitrate " and silver .
[tex]\mathrm{✌TeeNForeveR✌}[/tex]
Oxygen is a diatomic element.why give reason.
Answer:
Diatomic molecules contain two atoms that are chemically bonded. If the two atoms are identical, as in, for example, the oxygen molecule (O2), they compose a homonuclear diatomic molecule, while if the atoms are different, as in the carbon monoxide molecule (CO), they make up…
Explanation:
yei hoo arko aaxaina ...
6. Sometimes a tire that appears to be fine may be unsafe because: A. There may be perforations too small to see B. The manufacturing date may be incorrect C. Chemical reactions may have deteriorated the rubber
Answer:
C. Chemical reactions may have deteriorated the rubber
Explanation:
A tire ages with time and most of the time this happens due to chemical reactions in the rubber parts. This could happen faster due to heat and sun.
As a tire is deteriorating or aging, a chemical change happens. What happens is that more chemical bonds are going to be produced with time between the molecules. We call this the process of oxidation. This actually bad for the tire, because the rubber would turn out to be stuffs d strong causing the tires thread to separate and also disintegration would occur.
Will Mark Brainlest ( all the disaster are hazard but all the hazard are not disaster) give reason
Answer:
Explanation to the following question is as follows;
Explanation:
Any phenomenon that would have the potential to cause severe death or property damage is considered a danger. When the potential for devastation is realised, a hazard becomes a disaster. All catastrophes are risks, but not all risks are catastrophes. Hazards do not always result in devastation.
Answer:
I hope this will help you.
What element on the periodic table has 5 protons, 5 electrons, and 5 neutrons?
Answer:
Boron
Explanation:
this is your answer
O2 oxygen is diatomicO + O O=O Double Bond
Answer:
O 100
Explanation:
The mass of a boy is 60 kg. Calculate his weight if the value of g is 9.8 ms2
Answer:
Weight = mass × gravitational
Weight = 60 kg × 9.8 ms²
= 588 N
Explanation:
hope it helps
Weight of the boy = Mass of the boy × g
= 60 × 9.8
= 588kgm/s²
= 588N
1. How many ATOMS of boron are present in 2.20 moles of boron trifluoride ? atoms of boron.
2. How many MOLES of fluorine are present in 5.35*1022 molecules of boron trifluoride ? moles of fluorine.
Answer:
1. How many ATOMS of boron are present in 2.20 moles of boron trifluoride? atoms of boron.
2. How many MOLES of fluorine are present in of boron trifluoride? moles of fluorine.
Explanation:
The molecular formula of boron trifluoride is [tex]BF_3[/tex].
So, one mole of boron trifluoride has one mole of boron atoms.
1. The number of boron atoms in 2.20 moles of boron trifluoride is 2.20 moles.
The number of atoms in 2.20 moles of boron is:
One mole of boron has ---- [tex]6.023x10^2^3[/tex] atoms.
Then, 2.20 moles of boron has
-[tex]=2.20 mol. x 6.023 x 10^2^3 atoms /1 mol\\=13.25x10^2^3 atoms[/tex]
2. Calculate the number of moles of BF3 in 5.35*1022 molecules.
[tex](5.35x10^2^2 molecules/6.023x10^2^3)x 1mol\\=0.0888mol[/tex]
One mole of boron trifluoride has three moles of fluorine atoms.
Hence, 0.0888moles of BF3 has 3x0.0888mol of fluorine atoms.
=0.266mol of fluorine atoms.
As a pure element the oxidation number of zinc is ________, but in compounds such as ZnCO3 its oxidation number is ________. Group of answer choices
Answer:
0, +2
Explanation:
As a pure element, any element or simple compound has an oxidation number of 0. This makes it a lot easier, and can be applied for almost any element or compound that uses one atom, like F2, O3, Zn, Fe, etc. However, in compounds, Zinc's oxidation number tends to be +2, and this is just a rule that I memorized when I learned this topic. Please let me know if you still need help and I hope you understood!
As a pure element, the oxidation number of zinc is zero, but in compounds such as [tex]ZnCO_3\\[/tex] its oxidation number is +2.
What is the oxidation number?Oxidation number also called oxidation state, is the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.
As a pure element, any element or simple compound has an oxidation number of 0. This makes it a lot easier and can be applied for almost any element or compound that uses one atom, like [tex]F_2[/tex], [tex]O_3[/tex], Zn, Fe, etc.
However, in compounds, Zinc's oxidation number tends to be +2.
Learn more about the oxidation number here:
https://brainly.com/question/10079361
#SPJ2
this symbol (g) in a chemical formula indicates that
Answer:
indicates that the substance is in a gaseous state
A toy plane has a mass of 2.5kg and is 18 m above the ground. It is moving 4.5 m/s.
how much mechanical energy does the toy have?
A. 416J
B. 441J
C. 466J
D. 491J
Answer:
466J (c)
Explanation:
Mechanical Energy= Kinetic+Potential
Potential energy= mgh
Plug in givens
mgh=2.5*18*9.8=441J
Kinetic Energy = 1/2mv^2
Plug in givens
1/2mv^2= 1/2(2.5)(4.5)^2= 25.3125J
Mechanical energy= 441J+25.3125J=466.3125J or 466J
True or false, The atomic number of an element is a whole number that decreases as you read across each row of
the periodic table from left to right.