which among the following pairs are not isotopes?
help please bjfkboweugfowbs
Answer:
B is correct answer because The enthalpy is negative so this means the reaction produces heat and the reaction is exothermic
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 YOUWhat is the wavelength of a wave that has a frequency of 6.1 x 109 Hz ? c = λυ where c = 2.998 x 108 m/s
a. 20.4 m
b. 2.04 m
c. 0.49 m
d. 0.049 m
Answer:
Wavelength = 0.049 m
Explanation:
Given that,
The frequency of a wave,[tex]f=6.1\times 10^9\ Hz[/tex]
We need to find the wavelength of the wave. We know that,
[tex]c=f\lambda\\\\\lambda=\dfrac{c}{f}\\\\\lambda=\dfrac{2.998 \times 10^8}{6.1\times 10^9}\\\\\lambda=0.049\ m[/tex]
So, the wavelength of the wave is 0.049 m.
Select from below all elements that follow the DUET rule (not the octet rule). (you can select multiple)
a) Li
b) Mg
c) O
d)He
e) H
f) Ne
Help asappppp quickly only right answers aloud
Answer:
Inference
Explanation:
A conclusion reached on the basis of evidence and reasoning is called an inference.
Under the Controlled Substance Act (CSA), dispensing a controlled substance (CS) to the ultimate use includes ____________ (Select ALL that Apply)
Answer:.
pharmacies, prescribers, distributors/wholesalers, researchers, manufacturers, hospitals.
Explanation:
The Controlled Substance Act is a federal drug policy of the United States which regulates the manufacture, use, importation and possession and distribution of certain substances. It was enacted by the United States Congress in the year 1971.
Under the Controlled Substance Act, the dispensing of a controlled substance to the use includes pharmacies, prescribers, distributors/wholesalers, researchers, manufacturers, hospitals, etc.
what is 10x412x3021x13123
A solution of known concentration is called
Answer:
It is called standard solution.
Explanation:
I hope this helps! Have a nice dayy! :)
What are the steps for writing the formula for a molecular compound? Naming a molecular
compound?
Answer:
Your question was explained in my chemistry book so I just shared the picture
Hope that helps
Write the balanced chemical equation when carbonate ores are heated in a limited supply of air.
Answer:
MCO₃ (s) -> MO (s) + CO₂ (g)
Explanation:
M = a metal
This process is called calcination and is generally used to remove impurities. It's most common use is to remove carbon from limestone.
CaCO₃ (s) -> CaO (s) + CO₂ (g)
which states of matter can flow from one place to another
Answer:
Liquid
Explanation:
Quite an easy question!
Answer:
Liquid
Explanation:
I was passing by lol
Help ASAP only right answers only no spam don’t answer if you don’t know
Answer:
theory
Explanation:
if you assume something that you didn't see occuring it is called a theory
When a theory is disposed by further evidence, which of the following occurs
Answer:
it adds to scientific knowledge
A gas has density 2.41 g/liter at 25°C and 770 mm Hg. Calculate it's molecular mass (R = 0.0821 L atm.mol-1K-1.
ASAP!!!!!!!!!
Answer:
Molecular mass, M = 58.20 g/mol.
Explanation:
Given the following data;
Density = 2.41 g/literTemperature = 25°CPressure = 770 mmHgGas constant, R = 0.0821 L atm.mol-1K-1Conversion:
760 mmHg = 1 atm
770 mmHg = 770/760 = 1.0131 atm
Temperature = 25°C = 273 + 25 = 298 K
To find the molecular mass, we would use the ideal gas law equation (density version);
PM = dRT
Where;
P is the pressure.M is the molecular mass.d is the density of a substance.R is the ideal gas constant.T is the temperature.Making M the subject of formula, we have;
[tex] M = \frac {dRT}{P} [/tex]
Substituting into the formula, we have;
[tex] M = \frac {2.41 * 0.0821 * 298}{1.0131} [/tex]
[tex] M = \frac {58.9626}{1.0131} [/tex]
Molecular mass, M = 58.20 g/mol.
SI units is an improved version of MKS system.
Answer:
the S.I unit
Explanation:
is the best unite
Freé point
[tex] \: \: \: \: \: \: [/tex]
Answer
Tq so much.
Pls follow me and Mark as brainliest Plsssssssss
Answer:
Thank you so much.
If the sky is actually black, and the water is actually clear, where does the blue color for the sky and water come from?
Answer:
that the water is blue because of the way water absorbs light, the way particles in the water scatter light, and also because some of the blue light from the sky is reflected
Hydrogen fluoride, HF exist as liquid at room temperature. Explain this phenomenon based on the formation of hydrogen bonds.
Explanation:
The hydrogen fluoride molecule is highly polar, in the liquid and gaseous phases, HF prone to formation hydrogen bonds. ... These hydrogen bonds are strong, their energy is 41.5 kj/mol.Hydrogen fluoride can be a liquid or gas at room temperature; it has a boiling point of 19.5 ºC. It is corrosive, colourless and has a very strong odour.The gaseous compound formed when dry fluorine gas reacts with dry Hydrogen, gas is called hydrogen fluoride. Hydrogen fluoride gas on condensation forms liquid hydrogen fluoride which is also referred to as anhydrous hydrogen fluoride or anhydrous hydrofluoric acidhope it helps
stay safe healthy and happy..a beam balance is called a first class lever why?
Answer:
A beam balance is an example of a first class lever.
Explanation:
A beam balance is an example of a first class lever. In a first class lever, the fulcrum is between the effort (force) and the load. The effort (force) moves over a large distance to move the load a smaller distance.
Other examples of first class lever are pliers, scissors, a crow bar, a claw hammer, a see-saw and a weighing balance etc.
Blood tests can be used to check a person's blood glucose and hormone levels. The tabular column given below shows the result of two blood tests carried out on three people to check their blood glucose levels. Person 1 is healthy
Answer:
In after fasting test, Person 2 has slightly higher blood glucose level than person 1.
In after drinking glucose test, Person 3 has much high glucose level than person 1.
Explanation:
Blood sugar test determines the level of glucose present in body. The test can be taken after intake of food / glucose or after fasting for 12 hours. Results of both tests are compared to identify level of glucose present in human body. In after fasting test person has higher glucose and in another test person 3 has higher glucose level.
why are metal containers not used for storing acids
Answer : Metal containers are not used for storing acid because most of the time acid reacts with almost every metal and produces salts or oxides which alters the acid characteristics making it useless .......
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
Which of the following make up an atom of gold? Select all that apply.
a
photons
b
electrons
c
neutrinos
d
protons
e
neutrons
Answer:
b, d, e
Explanation:
An atom is made up of electrons, protons and neutrons. Gold is an atom thus has the above particles.
The charge on a charged sphere is concentrated at (or on) its ________.
Central Core
Interior
Surface
I ANSWERED IT BUT SOMEONE SYAYS ITS COPY SO WHAT COULD I DO ;(
Answer:
The charge on a charged sphere is concentrated at (or on) its central core .hope it is helpful to you
If 1000. mL of water freezes, which of the following is a reasonable approximation for the volume of the resulting ice?
Group of answer choices
1000. mL
961 mL
1040 mL
No answer text provided.
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Answer:
If 1000. mL of water freezes, which of the following is a reasonable approximation for the volume of the resulting ice?
Group of answer choices
1000. mL
961 mL
1040 mL
Explanation:
Ice is fewer denser than water.
The reason is the volume occupied by the same mass of ice with water is more than the volume occupied by water. Ice has more empty space within it.
Due to this reason, ice floats on water.
When 1000ml of water freezes to ice then its volume is greater than water.
Among the given options the correct answer is 1040 mL .
Help me please I need this quickly
9. melting point
10. balloons float because they are filled with hydrogen, a gas which is less dense than air.
11. specific gravity
12. element
13. mixture
14. sodium and chlorine
15. cutting of paper
16. condensation
17. 1 and 3
18. heat energy is released
The southernmost point of india is _____
(a) indra point
( b) Gulf
( c) Amaravati
(d) jarawas
Answer:
(a) indra pointExplanation:
Indira point is the southern most point of India and is situated on great nicobar island in the nicobar island.
Answer:
Your Ans Is
(A) Indra point.
How many mm of 0.200 M FeCl3 are needed to react with an excess of K2S to produce 2.75 g of Fe2S3 if the percent yield for the reaction is 65.0%?
Answer:
130 mL
Explanation:
2FeCl3(aq) + 3K2S(aq) -----> Fe2S3(s) + 6KCl(aq)
Percent yield = actual yield/theoretical yield × 100
actual yield = 2.75 g
Theoretical yield = x
65= 2.75/x × 100
x= 2.75 × 100/65
x= 4.2 g
Number of moles of FeCl3 = mass/molar mass = 4.2 g/ 162.2 g/mol = 0.026 moles
Then;
n= CV
n= number of moles
C= concentration
V= volume
V= n/C
V= 0.026 moles/ 0.200 M
V= 0.13 L or 130 mL
A 15.8 g sample contains 3.60 g F, 4.90 g H, and 7.30 g C. What is the percent composition of hydrogen in this sample?
Answer: 22.7848% F or 23%
Explanation: %F = 3.6g/15.8g • 100% = 22.7848% F
The percentage composition of hydrogen in the given sample is equal to 31%.
What is percentage composition?The percentage composition of a given compound can be described as the ratio of the quantity of each element to the total quantity of individual elements in the compound multiplied by 100. The quantity can be measured in terms of grams of the elements present in the sample.
The percent composition is expressed in its composition in terms of all the elements present. Thus, it helps in the chemical analysis of any given compound.
The percentage composition is expressed using the following formula,
Percentage composition of E = (E/T) × 100
Where E represents the total quantity of element E present in the compound and T represents the total quantity of all the elements present in the compound.
Given, the mass of the F, H, and C is 3.60g, 4,90 g, and 7.30 g respectively.
The total mass of the given sample = 15.8 g
The mass of the hydrogen in the sample = 4.90 g
The percent composition of H = (4.90/15.8) × 100 = 31 %
Therefore, the percent composition of hydrogen in this sample is 31%.
Learn more about percent composition, here:
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