Answer:
4.21
Explanation:
use Avogadro's number
6.023 x 10^23
multiply this by 7 because you want to find 7 moles :
6.023 x 10^23 x 7 = 4.21
Mole concept
Calculate the number of iodine atoms in 4.50g of iodine gas
Answer:
0.017g/mol
Explanation:
according to the mole concept to calculate the number of moles of a substance you use the formula
number of moles= mass/molecular mass
=4.5g/254g/mole
=0.017moles
I hope this helps and sorry if it's wrong
What happens when the temperature of a solid reaches its melting point?
O A. The kinetic energy breaks the bonds between atoms.
O
B. The kinetic energy exceeds the intermolecular forces.
O C. The kinetic energy within the molecules decreases.
O D. The kinetic energy reaches its maximum amount.
The kinetic energy exceeds the intermolecular forces.
This is the answer.
substance with 169 melting point
Answer:
the substance with 169 melting point is buten
Look at the two thermometers. Which statement explains which thermometer is more appropriate to measure the temperature of a liquid at 43.6 C
Answer:
I don't know
Explanation: Where are the statements?
can u plz solve it n send the answer
1. Cl2 + H2O → HOCl + HCl
2. Tooth decay starts when when the pH of the mouth is lower than 5.5. Tooth enamel is made up of calcium phosphate and it is one of the hardest substances of the body. But it is corroded when the pH is less than 5.5. The bacteria of our mouth produce acids by degradation of sugar and food particles remaining in our mouth after eating food.
3. Fluorine salts are added in toothpaste to protect our teeth from tooth decay. Fluorine salts are mildly basic, so they neutrelise the acid in our mouth that leads to tooth decay.
4. Tincture of iodine is iodine, pottasium iodide and sodium iodide dissolved in ethanol. Iodine acts in an antiseptic manner by destroying microbial proteins and DNA.
5. Tincture of iodine is clear and reddish brown liquid.
why water molecules remain associated in liquid water
Answer:
Answer: They are attracted to each other due to their electrostatic attraction. All that means is the hydrogen atom is positively charged, while the oxygen atom is negatively charged. ... The hydrogen of one water molecule will bond to the oxygen atom of another molecule.
Answer:
They are attracted to each other due to their electrostatic attraction. All that means is the hydrogen atom is positively charged, while the oxygen atom is negatively charged. ... The hydrogen of one water molecule will bond to the oxygen atom of another molecule.
Explanation:
how to prepare hydrogen gas
The equilibrium constant Kc for the reaction
N2 (g) + 3H2 (g) -> 2NH3 (g)
at 450°C is 0.159. Calculate the equilibrium composition
when 1.00 mol N2 is mixed with 3.00 mol H2 in a 2.00-L
vessel.
part 1: Enter the equilibrium concentration for N2.
part 2: Enter the equilibrium concentration for H2
part 3: Enter the equilibrium concentration for NH3.
Answer:
[N2] = 0.3633M
[H2] = 1.090M
[NH3] = 0.2734M
Explanation:
Based on the reaction of the problem, Kc is defined as:
Kc = 0.159 = [NH3]² / [N2] [H2]³
Where [] are the equilibrium concentrations.
The initial concentrations of the reactants is:
N2 = 1.00mol / 2.00L = 0.500M
H2 = 3.00mol / 2.00L = 1.50M
When the equilibrium is reached, the concentrations are:
[N2] = 0.500M - X
[H2] = 1.50M - 3X
[NH3] = 2X
Where X is reaction quotient
Replacing in the Kc equation:
0.159 = [2X]² / [0.500 - X] [1.50 - 3X]³
0.159 = 4X² / 1.6875 - 13.5 X + 40.5 X² - 54 X³ + 27 X⁴
0.268313 - 2.1465 X + 6.4395 X² - 8.586 X³ + 4.293 X⁴ = 4X²
0.268313 - 2.1465 X + 2.4395 X² - 8.586 X³ + 4.293 X⁴ = 0
Solving for X:
X = 0.1367. Right solution.
X = 1.8286. False solution. Produce negative concentrations
Replacing:
[N2] = 0.500M - 0.1367M
[H2] = 1.50M - 3*0.1367M
[NH3] = 2*0.1367M
The equilibrium concentrations are:
[N2] = 0.3633M[H2] = 1.090M[NH3] = 0.2734M
2.5 kilogram into gram
Answer:
2500grams
hope this helps
Answer: 2500 gram
Explanation:
Concept:
Here, we need to know the idea of unit conversion.
Unit conversion is the conversion between different units of measurement for the same quantity, typically through multiplicative conversion factors.
1 kg = 1000 g
Solve:
1kg = 1000g
2.5kg = 2.5 × 1000 = 2500g
Hope this helps!! :)
Please let me know if you have any questions
Answer in detail?? What precautions would you take to protect yourself from an earthquake, when you are at home and when you are outdoors?
Answer:
If you're indoors, stay inside. If you're outside, stay outside. If you're indoors, stand against a wall near the center of the building, stand in a doorway, or crawl under heavy furniture (a desk or table). Stay away from windows and outside doors.
Answer
Protect your head and neck with a large book, a pillow, or your arms. The goal is to prevent injuries from falling down or from objects that might fall or be thrown at you.If you are able, seek shelter under a sturdy table or desk. Stay away from outer walls, windows, fireplaces, and hanging objects.If you are unable to move from a bed or chair, protect yourself from falling objects by covering up with blankets and pillows.If you are outside, go to an open area away from trees, telephone poles, and buildings, and stay there.what protects the cells of plants
Explanation:
Plant cells have several structures not found in other eukaryotes. In particular, organelles called chloroplasts allow plants to capture the energy of the Sun in energy-rich molecules; cell walls allow plants to have rigid structures as varied as wood trunks and supple leaves; and vacuoles allow plant cells to change size.
The cell wall is located outside the cell membrane. It consists mainly of cellulose and may also contain lignin , which makes it more rigid. The cell wall shapes, supports, and protects the cell. It prevents the cell from absorbing too much water and bursting.
What is the change in enthalpy of the first reaction below, given the enthalpies of the other two reactions?
Here's the reactions:
There was a formatting issue with the specific chemistry symbols, there all correct in the picture below
2C(s) + O2(g) → 2CO(g)
C(s) + O2(g) → CO2(g) ∆H0= -394 KJ/mol
CO(s) + 1/2 O2(g) → CO2(g) ∆H0= -283 KJ/mol
There was a formatting issue with the specific chemistry symbols, there all correct in the picture below
Answer:
∆H0 = -222kJ/mol
Explanation:
Using Hess's law, we can find the ΔH of a reaction from the sum of another related reactions as follows:
Using the reactions:
(1) C(s) + O2(g) → CO2(g) ∆H0= -394 KJ/mol
(2) CO(s) + 1/2 O2(g) → CO2(g) ∆H0= -283 KJ/mol
Twice (1):
2C(s) + 2O2(g) → 2CO2(g) ∆H0= 2*-394 KJ/mol = -788kJ/mol
The inverse reaction of (2):
-(2) CO2(g) → CO(g) + 1/2 O2(g) ∆H0= 283 KJ/mol
Twice this reaction:
2*-(2) 2CO2(g) → 2CO(s) + O2(g) ∆H0= 2*283 KJ/mol= 566kJ/mol
Now, the sum of 2*(1) - 2*(2) produce:
2C(s) + 2O2(g) + 2CO2(g)→ 2CO2(g) + 2CO(g) + O2(g) ∆H0= -788kJ/mol + 566kJ/mol
Subtracting the molecules that ar in both sides of the reaction:
2C(s) + O2(g) → 2CO(g) ∆H0 = -222kJ/mol
Please hurry this is due tomorrow morning
A student is studying the ways different elements are similar to one another. Diagrams of
atoms from four different elements are shown below.
Which two atoms are of elements in the same group in the periodic table?
F Atom 1 and Atom 2
G Atom 1 and Atom 4
H Atom 2 and Atom 3
J Atom 3 and Atom 4
Iupac name for this?
Answer:
Explanation:
4,5 diethyl-2 fluoro-3-methylheptanal
Which of the following statements about periodic trends is true?
O both electronegativity and atomic radius decrease from bottom to top and from left to right on
the periodic table.
O both electronegativity and ionization energy increase from bottom to top and from left to right
on the periodic table.
O both atomic radius and ionization energy increase from bottom to top and from right to left on
the periodic table.
O electronegativity, ionization energy and atomic radius all decrease from bottom to top and from
left to right on the periodic table.
both electronegativity and ionization energy increase from bottom to top and from left to right
on the periodic table.
Some one please Help and Thank you
Answer:
C is the correct answer
Explanation:
most probably
What was the main aim of Cavendish’s work?
Answer:
The Cavendish experiment, performed in 1797–1798 by English scientist Henry Cavendish, was the first experiment to measure the force of gravity between masses in the laboratory and the first to yield accurate values for the gravitational constant
Explanation:
I think that's correct
The air you breathe is a solution of about 78% nitrogen and 21% oxygen and 1% other
gases. Which substance is the solvent? Explain how you know
Answer:
I believe nitrogen would act as the solvent, I know this because there is a higher percentage of it than oxygen and other.
In the air composition provided, nitrogen is the solvent, while oxygen and the other gases are the solutes dissolved within the nitrogen solvent.
In a solution, the solute is the substance that is present in a smaller quantity and is dissolved in a larger quantity of another substance called the solvent. The solute may dissolve in the solvent to create a homogeneous mixture.
In the given case, air is a mixture of gases, and the major components are nitrogen (78%) and oxygen (21%), with a small percentage of other gases (1%). Here, nitrogen and oxygen are the solutes, and the remaining gases are also solutes, but in a smaller proportion.
The solvent is the component that dissolves the solute, and in the case of air, nitrogen is acting as the solvent. Nitrogen, being the most abundant gas in the mixture, forms the "base" or "carrier" for the other gases to be mixed within. Oxygen and the other gases dissolve or mix into nitrogen gas, creating a homogeneous mixture that we breathe.
Thus, in the air composition provided, nitrogen is the solvent, while oxygen and the other gases are the solutes dissolved within the nitrogen solvent.
Learn more about the solvents here:
https://brainly.com/question/11985826
#SPJ3
you have read in chapter 1 that the Parliamentary form of Government that is used in India has three tier this includes the Parliament control Government and the various state legislative state government fill in the following table with the information on the various represent it is from your area
Answer:
[tex]\begin{array}{lll}&State \ Government&Central \ Government\\Political \ parties \ in \ power&PDP&PDP\\Present \ area \ representative & Jude \ Ogbimi&Leo \ Ogor \\Opposition \ party&APC&APC\\Date \ of \ election&April \ 10 \ 2021&February\ 23\ 2019\\Date \ of \ next \ election&April \ 2025&February \ 2023\\Number \ of \ women&2&Non\end{array}[/tex]
Explanation:
The People's Democratic Party, PDP, are the party in power in the Delta state House of Assembly, while the All Progressives Congress, APC, are the opposition party
Ethylene glycol (antifreeze) has a density of 1.11 g/cm^3. What is the volume (in m^3) of 9.7 tons?(1 ton = 2.000*10^3lb; 1 kg= 2.2046 lb
Answer: The volume of 9.7 tons of given ethylene glycol is 0.0079 [tex]m^{3}[/tex].
Explanation:
Given: Density = 1.11 [tex]g/cm^{3}[/tex]
Mass = 9.7 tons
Convert tons into lb as follows.
[tex]1 ton = 2 \times 10^{3} lb\\9.7 ton = 9.7 ton \times 2 \times 10^{3} \frac{lb}{1 ton}\\= 19.4 \times 10^{3} lb[/tex]
Now, lb is converted into kg as follows.
[tex]1 kg = 2.2046 lb\\1 lb = 0.453592 kg\\19.4 \times 10^{3} lb = 19.4 \times 10^{3} lb \times 0.453592 \frac{kg}{1 lb}\\= 8.79 kg[/tex]
1 kg = 1000 g
So, 8.79 kg = 8790 g
Density is the mass of a substance divided by its volume. Hence, volume of ethylene glycol is calculated as follows.
[tex]Density = \frac{mass}{volume}\\1.11 g/cm^{3} = \frac{8790 g}{volume}\\volume = 7918.92 cm^{3} (1 cm^{3} = 10^{-6} m^{3})\\= 0.0079 m^{3}[/tex]
Thus, we can conclude that the volume of 9.7 tons of given ethylene glycol is 0.0079 [tex]m^{3}[/tex].
PLEASE HELP ASAP!! {40 POINTS}
Classify EACH possible hypothesis about a medical aloe Vera plant as falsifiable or non-falsifiable
A) Aloe Vera gel is the best natural skin moisturizer.
B) Aloe Vera gel can heal wounds by boosting cell renewal.
C) Aloe Vera juice tastes better than carrot juice.
D) Drinking aloe juice can reduce the risk of lung cancer.
Answer:
The correct answer is -
FALSIFIABLE:
Aloe vera gel can heal wounds by boosting cell renewal.
Drinking aloe juice can reduce the risk of lung cancer.
NON-FALSIFIABLE:
Aloe vera gel is the best natural skin moisturizer.
Aloe vera juice tastes better than carrot juice.
Explanation:
Falsifiable is the ability or chances of any hypothesis, claim or statement to be proved wrong. In such a hypothesis, it is possible to carry an experimental observation that disproves the idea in claim or question.
In the given examples
Aloe vera gel can heal wounds by boosting cell renewal.
Drinking aloe juice can reduce the risk of lung cancer.
There is no observation in the favor of the claim so there more likely to be falsifiable whereas, Aloe vera gel is the best natural skin moisturizer.
Aloe vera juice tastes better than carrot juice are more non-falsifiable as these are based on personal choice or experimental observation.
Answer:
FALSIFIABLE IS *DOWNARROW
Aloe vera gel can heal wounds by boosting cell renewal.
Drinking aloe juice can reduce the risk of lung cancer.
NON-FALSIFIABLE IS *DOWNARROW*
Aloe vera gel is the best natural skin moisturizer.
Aloe vera juice tastes better than carrot juice.
Explanation:
yes
calculate the mass of magnesium needed to make 25g of magnesium oxide
mark brainliest of correct xx
Answer:
15g
Explanation:
First, you need to correct the answer to the previous question. The percentage by mass of Mg in MgO =
Mg = 24.3 amu
O = 16.0 amu
The total mass of MgO = 40.3 amu
To calculate the percent composition of Mg:
% = 24.3/40.3 x 100
% = 60
To calculate the mass of Mg needed to make 25g of MgO:
x/25g = 60%/100%
100x = (25)(60)
100x = 1500
x = 15g
When a vacancy exists in an inner electron shell of an atom (as a result of photoelectric effect, Compton scattering, or bombardment by other electrons), the energy liberated when this vacancy is filled, instead of emerging from the atom as fluorescent radiation, can be transferred to another electron of the atom, thereby ejecting the electron. Such an emitted electron is called a(n) _____ electron
Answer:
The answer is "Auger".
Explanation:
The Auger effect is an effect size when the vacancy of even an atom throughout the inner shell was complemented by the release of even an electron from the same atom. Whenever a central electron is lost, a higher energy level electron can drop into the void and release energy, which can be the result.
Plz Help I have One more time To retake and I can't fail it..
Answer:
A
Explanation:
Hydrogen bonds are intermolecular forces of interaction that exist between molecules of a substance in which hydrogen is bonded to a highly electronegative atom. Hydrogen bonds are strong intermolecular forces and account for high melting and boiling points of small molecules such as water. They stem from dipole-dipole interaction between molecules of a substance.
Metallic bonds are bond forces which exist in a metal. Metal cations are held together by a sea of electrons via electrostatic interaction.
The ionic bond is formed by transfer of electrons from one atom to another leading to the formation of an ion pair held together by electrostatic attraction.
Metallic bonds and hydrogen bonds are much weaker than ionic bonds. Ionic compounds are known to have high melting and boiling points.
Any shipment of peanuts that contains more than 25 ppb of this dangerous fungus is rejected. A company receives 24 t of peanuts to make peanut butter. What is the maximum mass, in g, of fungus that is allowed? Hint 1 t = 1000 kg.
Answer:
0.60g of the fungus can be allowed
Explanation:
The maximum concentration of the fungus that can be allowed is 25 ppb, that is 25mg/t.
As the peanuts are 24t, the mass of fungus that can be allowed is:
24t * (25mg/t) = 600mg of the fungus can be allowed. In grams are:
600mg * (1g/1000mg) =
0.60g of the fungus can be allowedAnswer:
0.5g of toxin
Explanation:
ppb = mass of solute/ mass of solution x 10^9
ppb = mass of fungus/ mass of peanuts x 10^9
25ppb = (x/2 x 10^7g) x 10^9
x = (25)(2 x 10^7g)/ 10^9
x = 0.5g of toxin
x represented the unknown mass of solute (fungus), in which we solved for. We already knew we were using the ppb formula, which is mass of solute/ mass of solution x 10^9, because the question mentions that there are 25ppb of peanuts in the shipments. In the calculations, you can see that I substituted the mass of peanuts with 2 x 10^7g. I did this because the question mentions that there are 20t of peanuts and since each t = 1000kg, I multiped 20 x 1000 to get 20 000kg. In my formula for ppb, I know that I have to use grams of solution, not kilograms. Knowing this, we follow the formula for ppb and substitute our known values and solving for unknown values.
how many Molecules and atoms of the product 2H2O+ O2
Answer:
A water molecule is composed of two hydrogen atom and one oxygen atom but you can't simply take two hydrogen atom stick them onto an oxygen atom
what is depletion??
good morning have A crazy day
Explanation:
reduction in the number or quantity of something.
"the depletion of the ozone layer" is called depletion
A science student observes that a dissolvable antacid tablet acts faster in relieving stomach pain when taken with warm water than when taken with water at room temperature. Based on the observation, suggest a potential problem that can be studied. Also, list the dependent, independent, and controlled variables that can exist in such an investigation.
Answer:
We know that an antacid is a base that can neutralize the stomach acid when ingested. The student observed that a soluble antacid tablet reacted faster in relieving pain due to the excess acid secreted in the stomach. So, the problem that can be studied is the effect of temperature on the rate of neutralization of stomach acid by the antacid. The independent variable is the one the student is going to vary that is the temperature. The dependent variable is the rate of reaction or the time taken for an antacid tablet to neutralize the acid present in stomach. The controlled variable is the tablet taken, that is the student should use a specific antacid tablet to ensure that the rate of reaction or the time taken for the antacid tablet to neutralize the acid present in stomach is not affected by the chemical composition of tablet.
Explanation:
Hope u understood.
How do the substances compare?
Formula of Potash Alum
Answer:
KAl(SO₄)₂·12H₂O
Explanation:
cuz math
