Answer:
One orbital
Explanation:
There is only one orbital in the first energy level of any atom of an element.
What is energy level?Electrons present in an atom revolve in different orbits which are stationary states and are also called as energy levels. The energy levels are numbered as integers which are also called as principal quantum numbers.
Energy of the stationary state is given as E= -R
1/n² where R
is the Rydberg's constant. When an electron is excited, and it moves from lower to higher energy levels there is absorption of energy, while when it moves from higher energy level to lower energy level it radiates or gives out energy in the form of radiation.
They can also be defined as the distances between electron and nucleus of an atom . Electrons present in K energy level have least energy .Energy level diagrams are studied to understand nature of bonding , placement of electrons in orbits and and elemental behavior under certain conditions.
Learn more about energy level,here:
https://brainly.com/question/17396431
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Which types of particles are found in the nucleus of the atom?
Answer:
Protons and neutron are found in the nucleus.
Answer:
The nucleus of the atom contains two types of subatomic particles: protons(have a positive electrical charge) and neutrons (have no electrical charge).
please someone should explain gas laws to me
Answer:
Gas laws, Laws that relate the pressure, volume, and temperature of a gas. ... These two laws can be combined to form a single generalization of the behavior of gases known as an equation of state, PV = nRT, where n is the number of gram-moles of a gas and R is called the universal gas constant.
Explanation:
Hope it helps
What is the MSDS? Why is it important? *
Answer:
Hey there!
A MSDS is a Material Safety Data Sheet, and can be used to provide detailed and comprehensive information about the hazards of a certain product, such as medicine or chemicals.
Let me know if this helps :)
In a oxidation–reduction reaction, oxidation and reduction must occur simultaneously. Is this statement true or false?
Answer:
True
Explanation:
Oxidation and reduction always occur simultaneously. Gave example when a substance is oxidized or reduced? 1) The substance gaining oxygen or losing electron is oxidized. 2) The substance losing oxygen ( or gaining electron) is reduced. hope this helps you :)
5) What is the empirical formula of a compound containing 47.37% carbon, 10.59% hydrogen, and 42.04% oxygen?
Answer:
C2H4O
two atoms of carbon four atoms of hydrogen and one atom of oxygen
You buy several bags of balloons. On the package, it says that each bag has 100 balloons. He opens the bags and only one of them has 100 balloons inside; the other bags either have too many or too few. How would you describe this sample of bags?
Answer:
Accurate but not precise
Explanation:
The sample of balloon bags can be described as being accurate but not precise.
Recall that accuracy is the closeness of measurements to their true values while precision is the closeness of repeated measurement.
The balloon bags are accurate because it appears that the number of balloons in each bag is not far from the actual number of balloons that should be in them - exactly 100 in one and a few off in others. By the time the average number of balloons is calculated, it will not be far off from 100, if not exactly 100.
However, the sample bags are described as not being precise because of the inconsistency or lack of closeness in the number of balloons in each of them.
Ethylene glycol (C2H6O2) is used as an antifreeze in cars. If 400 g of ethylene glycol is added to 4.00 kg of water, what is the molality? Calculate how much the freezing point of water will be lowered. The freezing-point depression constant for water is Kf = –1.86°C/m.
Answer:
The freezing point of water will be lowered 3°C
Explanation:
Remember that molality is generally the standard for calculating the concentration, between molarity and molality. In this question we have to apply molality, given the units as moles and kilograms.
We can start by receiving the molality of this solution through the following formula...
[tex]\mathrm{m}=\mathrm{(mass}\mathrm{/molar\:mass)} * (1000/\mathrm{mass\:of\:solvent)},[/tex]
[tex]\mathrm{m} =\mathrm{(400.0 g / 62.07 g/mol) * (1000 / 4000.0 g)},[/tex]
[tex]\mathrm{m} = (400/62.07) * (1000 / 4000) = \left(\frac{400}{62.07}\right)\left(\frac{1000}{4000}\right) = \frac{1000}{620.7} = 1.61108\dots\mathrm{m}[/tex]
Now we can determine how much the freezing point of water will be lowered, given that the freezing-point depression constant for water is Kf= –1.86°C/m. Remember that " Kf " is the final temperature, so to determine how much the temperature of the water will decrease, we can note the change in temperature...
[tex]\mathrm{change\:in\:temperature} = ( - 1.86\mathrm{C/m})(1.61\mathrm{m}) = - 1.86 * 1.61 = -2.9946[/tex]
[tex]-2.9946 = \mathrm{About\:-3C}[/tex]
Hence the freezing point of water will be lowered 3°C.
what instrument should we use if we had to carry out a small reaction
Answer:
This question appears incomplete
Explanation:
However, a glassware/instrument that is used to carry out small reactions is a beaker. It is a cylindrical instrument usually made of glass (so as not to take part in the reaction). It can also be put over a bunsen burner to heat up its content in the process of a chemical reaction. It is quite ideal for small reactions.
chemical synthesis of drugs allowed development of cancer treatments that save lives
Answer:yes
Explanation:
What is the formal thought process of science?
Answer:
In science, you are looking for something and you discovered something else. This leads to many discovery among the world.
Find the density of a substance that’s had a volume of 24.7mL and a mass of 49.1g. Give the answer with two decimals.
Answer:
1.99 g/mL
Explanation:
Use the formula d = m/v, where m is the mass and v is the volume.
Plug in the values:
d = 49.1/24.7
d = 1.99 g/mL
Answer:
About 1.99 g/mL
Explanation:
The density of a substance can be found using the following formula:
d= m/v
where m is the mass and v is the volume.
The mass of this substance is 49.1 grams and the volume is 24.7 milliliters.
m= 49.1 g
v= 24.7 mL
Substitute these values into the formula.
d= 49.1 g / 24.7 mL
Divide 49.1 g by 24.7 mL
d= 1.98785425 g/mL
We are asked to round to two decimal places, or the hundredth place. The 8 in the thousandth place tells us to round the 8 to a 9 in the hundredth place.
d ≈ 1.99 g/mL
The density of the this substance is approximately 1.99 grams per milliliter.
Answer in the correct significant figures: 9.66 / 0.33
ΔH for the reaction below is -826.0 kJ/mol. Calculate the heat change when a 69.03-g sample of iron is reacted.4Fe(s) + 3 O2(g) --> Fe2O3(s)a. - 255.2 kJb. -510.5 kJc. -1020.9 kJd. -2042 kJe. -2.851 x 10^4 kJ
Answer:
c. -1020.9 kJ
Explanation:
4Fe (s) + 3 O₂ (g) --> 2 Fe₂O₃(s) ΔH = -826.0 kJ/mol.
atomic weight of iron = 56
69.03 g = 69.03 / 56
= 1.23268 moles
Heat released by 1.23268 moles
= 1.23268 x 826.0
= -1020.9 kJ .
what are a few examples of what energy is?
✅Energy exists in many different forms✅
Examples of these are: light energy, heat energy, mechanical energy, gravitational energy, electrical energy, sound energy, chemical energy, nuclear or atomic energy and so on. Each forms can be converted or changed into the other forms.
IamSugarBee
Which of the following questions can be answered by science?
a
What is the composition of air?
b
Should the driving age be reduced?
c
What is the purpose of our existence on Earth?
d
Should students be allowed to bring toys to school?
Answer:
(a), (b) and (c) I guessAnswer:
A. What is the composition of air?, B. Should the driving age be reduced?, D.
Should students be allowed to bring toys to school? Answer: A,B,D.
Convert 7.72 years into days.
Answer:2817.8
Explanation:multiply the value by 365
Explanation:
7.72 x 365= 2817.8 days
As the mass of a sample increases, the number of moles present in the sample
Answer:
increases
Explanation:
Answer: will also increase
Explanation:
If the mass in a sample increases, the number of molecules will also increase. Hope this helps!
The atoms and molecules in a liquid are in constant motion. As temperature decreases, what is true of the particles in the liquid? (5 points)
Oa
The distance between the particles increases.
The attraction between the particles decreases.
Ob
Ос
The rate of partide movement decreases.
Od
The potential energy of the particles decreases
Answer:
A
Explanation:
Answer:
The distance between the particles increases
HELP! What is a pure substance salt or seawater???? PLEASE HELP ME!
Answer:
Your answer is salt. Pure substances are made of materials with one type of molecule. Seawater has salt and water molecules, which is more than one, so your answer is salt.
Hope this helps!
Please help lol I dont understand it...
Answer:
It just means that you are supposed to find an object that is not used in a vacuum. For example, a hair-brush is not use in a vacuum lol
A paper clip released gently into the liquid settles at the bottom of the cylinder. What best compares the densities of the substances?
The clip is denser than the three liquids, and water is denser than oil.
Oil is denser than water but less dense than the clip.
Corn starch is denser than the other liquids and the clip.
Oil is denser than the other liquids, and all liquids are denser than the clip.
Answer:
C.
Explanation:
Objects and liquids float on liquids of a higher density and sink through liquids of lower density. the water and corn starch sank under the oil as well so that means they are denser. The paper clip sank through all three liquids also. Hence, the answer would be the clip is denser than the three liquids, and water is denser than oil.
does the atomic mass come from the masses of both protons and electron
Answer:
no
Explanation:
For any given isotope, the sum of the numbers of protons and neutrons in the nucleus is called the mass number. This is because each proton and each neutron weigh one atomic mass unit . By adding together the number of protons and neutrons and multiplying by 1 , you can calculate the mass of the atom.
Answer:
No
Explanation:
An element's mass number (A) is the sum of the number of protons and the number of neutrons. Protons and neutrons both weigh about one atomic mass unit or amu. Isotopes of the same element will have the same atomic number but different mass numbers.
Density Practice
Answer the following questions about density.
1) Density is based on the
and the
of a material
2) A material with a low density tends to
I
3) A material with a high density tends to
4) Bobbing for apples is a game where people try to bite apples from a bucket of water. While in the
water, the apples float. Which is less dense, the apples or the water?
5) A cannonball rolls off of a pirate ship and sinks to the bottom of the ocean. Which was more dense, the
cannonball or the ocean water?
Answer:
1) mass and volume
2) float.
3) Sink
4) Apples
5) Cannonball
Explanation:
1) Density is based on the mass and volume of a material.
2) A material or an object with low density than water or liquid tends to float.
3) A material or an object with high density than water or liquid tends to sink.
4) The apples in the water have less density as they are floating in the water.
5) The cannonball is more dense than the ocean water and the ball sink in the less density water.
3 Select the correct answer. Which unit can be used to express the rate of a reaction? A. mL / s B. mL / g C. g / mL D. mL / mol E. s / mL Reset Next
Answer:
A) mL / s
Explanation:
You are attempting to determine the thermodynamic properties of an unknown compound. You’ve already determined delta H fusion to be 5.56 kJ/mol and delta H vaporization to be 21.99 kJ/mol. In one of these previous experiments, 2.56 g of this compound was placed in a glass bulb and vaporized by placing the glass bulb into 200. g of hot water initially at 68.25 degrees Celsius, which resulted in a final water temperature of 67.91 degrees Celsius. You are now attempting to determine the enthalpy of solution of this compound. To this end, you dissolve 55.6 g of this compound in 495 g of water initially at 25.2 degrees Celsius. The final temperature of the solution is 19.4 degrees Celsius. What is the enthalpy of solution of this compound in kJ/mol?
Answer:
The heat of solution of the compound = 42.75 kJ/mol
Explanation:
Here we have;
The heat of vaporization = 21.99 kJ/mol
2.56 g of the compound is then placed in 200 g. of water
The temperature of the water reduces from 68.25°C to 67.91°C
The specific heat capacity of water = 4.19 kJ/kg = 4.19 J/g
Mass of the water = 200 g
Heat lost by the water ΔH = m × c × Δθ = n × ΔH vaporization of the compound
Where;
m = The mass of the water = 200 g
c = The specific heat capacity of water = 4.19 kJ/kg = 4.19 J/g
Δθ = The change in temperature = 68.25°C - 67.91°C = 0.34°C
n = The number of moles of the compound
ΔH = m × c × Δθ = 200×4.19×0.34 = 284.92 J = 0.28492 kJ
∴ n × ΔH vaporization of the compound = 0.28492 kJ
n = 0.28492 kJ/( ΔH vaporization of the compound) = 0.28492/21.99≈0.013 moles
∴ 2.56 g = 0.013 moles
1 mole = The molar mass of the compound = 2.56/0.013= 197.6 g/mol
Therefore;
The number of moles in 55.6 g of the compound = 55.6/197.6 = 0.2814 moles
The heat given by the water = ΔH = 495 × (25.2 - 19.4) × 4.19 = 12029.49 J
Therefore;
0.2814 × ΔH(solution) = 12029.49 J = 12.02949 kJ
ΔH(solution) = 12.02949/0.2814 = 42.75 kJ/mol
The heat of solution of the compound = 42.75 kJ/mol.
Sugar when dissolved into water, propose whether the compound forms atoms, molecules or lattices. Justify you answer
Answer:
atoms
Explanation:
for sugar to dissolve in water hydaration must be equal to or greater than the lattice energy or molecular forces so when the molecular forces breaks new atoms are formed for recombination in new compound
explain formation of covalent bonds when atoms share electrons.
Answer:
Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outer most (valence) electrons, atoms can fill up their outer electron shell and gain stability.
Explanation:
2.Which of the following compounds when dissolved in water will turn blue litmus paper red? copper oxide, calcium oxide, sulphur oxide, sodium oxide, iron oxide
Answer:
Sulphur oxide
Explanation:
All of the above oxides with the exception of sulphur oxide are basic oxides and so will not turn blue litmus paper red when dissolved in water. Sulphur oxide, SO2 on the other hand, is an acid anhydride (a non-metallic oxide which dissolves in water to produce acid) rendering it the ability of turning blue litmus paper red when dissolved in water.
Answer:sulpher oxide
Explanation:
All of the compounds except sulpher dioxide are metallic oxide which means basic oxide and base change red litmus paper to blue while acid change blue to red so the answer is the acidic oxide or sulpher dioxide
What is the iupac name of this structure?
Answer:
3–ethyl–4–methylhexane.
Explanation:
To name the above compound, do the following:
1. Determine the functional group of the compound.
2. Locate the longest continuous carbon chain. This gives the parent name of the compound.
3. Identify the substituent group attached to the compound.
4. Give the substituent the lowest possible count.
5. Combine the above to name the compound.
Now, we shall name the compound given in the question above as follow:
1. The compound contains only single bond. Therefore, the compound belong to the alkane family.
2. The longest continuous carbon chain is 6 i.e hexane.
3. The substituent group attached are:
i. Methyl, CH3.
ii. Ethyl, CH2CH3.
4. we shall name the substituents alphabetically i.e ethly will come before methyl. Therefore,
Ethyl is located at carbon 3.
Methy is located at carbon 4.
5. Therefore, the name of the compound is:
3–ethyl–4–methylhexane.
For an experiment, you are required to prepare a series of three solutions by diluting a cobalt(II) chloride stock solution. After making each solution, you notice that each is a different shade of pink. Which is the most concentrated?
a. the lightest pink solution you prepared
b. the darkest pink solution you prepared
c. the medium pink solution you prepared
d. the stock solution
Answer:
The stock solution
Explanation:
When preparing a series of solutions from a stock solution, the stock solution will always be the most concentrated solution of the set. Each of the subsequent solutions are prepared by dilution, which entails adding solvent to a portion of the stock solution. This will always result in a solution that is less concentrated than the stock solution.