Answer:
moles = no. of molecules / Avogadro's number
= 2.26 x 10^33 / 6.022 x 10^23
= 3752906011
Round to significant figures which is 3 = 3.75 x 10^9 mol
Explanation: The formula for finding how many moles of a substance when given the amount of molecules is: moles = number of molecules / Avogadro's number
does anyone wanna help me with my question for chemistry [i'll comment the question to you lol someone keeps sending links into my questions]
Answer:
same I was looking for a question like this I was asking question and someone kept commenting this bitly thing i dont kno I though it was just weird and frustrating lol
All matter has:
volume
mass
density
all of the above
One advantage to using nuclear power is —
it produces no air pollution
it is hard to store and dispose of the waste
the expense of constructing nuclear reactors
the threat of an accident
Answer:
it produces no air pollution
Sometimes the number of electrons in an atom changes. These atoms are called what
Answer:
ions
Explanation:
Stoichiometry
1. Based on the equation, Mg+2NaF => MgF2 + 2Na , if 23.56 grams of magnesium reacts with sufficient sodium
fluoride, how many grams of sodium will be produced?
Since we have sufficient sodium fluoride (NaF), the magnesium (Mg) will be our limiting reactant, and we will use its coefficient in the balanced equation to determine our molar ratio between the product of interest which, in this case, is sodium (Na).
We are given the mass of magnesium, 23.56 grams, which we must convert to moles by dividing the mass by the molar mass of magnesium: (23.56 g)/(24.305 g/mol) = 0.9693 mol Mg.
According to the balanced equation given, the molar ratio between sodium and magnesium is 2:1. That is, for every 2 moles of Na that are produced, one mole of Mg is consumed or reacted. The upshot is that the number of moles of sodium produced will be double the number of moles of Mg reacted. Since we have 0.9693 moles of Mg available to react, we will obtain (0.9693 mol Mg)(2 mol Na/1 mol Mg) = 1.939 mol Na.
Finally, we multiply our moles of sodium by the molar mass of sodium to get the mass: (1.939 mol Na)(22.99 g/mol) = 44.57 grams Na.
So, 44.57 grams of sodium will be produced.
The answer is given to four significant figures.
Convert 5 pounds to kilograms
Help me pleaseeee
Answer:
2.268
Explanation:
5 lb × 0.45359237 = 2.26796185 kg
How to convert Pounds to Kilograms
1 pound (lb) is equal to 0.45359237 kilograms (kg).
1 lb = 0.45359237 kg
The mass m in kilograms (kg) is equal to the mass m in pounds (lb) times 0.45359237:
m(kg) = m(lb) × 0.45359237
Example
Convert 5 lb to kilograms:
m(kg) = 5 lb × 0.45359237 = 2.268 kg
Hope this helped!!!
Answer:
2.26796 kg
Explanation:
The decay of radioactive elements occurs at a fixed rate. The half-life of a radioisotope is the time required for one half of the amount of unstable material to degrade into a more stable material. The half-life of Carbon-14 is 5,730 years. Choose ALL the true statements regarding the Carbon-14 isotope. A) 100 grams of C-14 decays to 25 grams in 11,460 years. B) The C-14 isotope is only useful for dating fossils up to about 50,000 years old. C) A sample contained 3,360 atoms of C-14. 8 half-lives passed and 210 C-14 atoms remained. D) If an ancient bone contains 6.25% of its original carbon, then the bone must be 22,920 years old. E) A sample of 4,000 radioactive C-14 atoms undergoes decay. After 5 half-lives there are 800 radioactive atoms remaining.
Answer:
100 grams of C-14 decays to 25 grams in 11,460 years.
The C-14 isotope is only useful for dating fossils up to about 50,000 years old
If an ancient bone contains 6.25% of its original carbon, then the bone must be 22,920 years old.
Explanation:
We already know that the half life of C-14 is 5,730 years. After the first half life, we have 50 grams remaining. This takes 5,730 years. After the second half life (11,460 years now gone) we have 25 grams of C-14 left.
If a fossil material is older than 50,000 years an undetectable amount of 14C is left in the sample hence Carbon-14 is no longer suitable for dating the sample.
From;
0.693/5730 = 2.303/t log (No/0.0625No)
Where;
t = time taken and No = initial amount of C-14
0.693/5730= 2.77/t
t = 22,920 years
A voltaic cell with a basic aqueous electrolyte is based on the oxidation of Cd(s) to Cd(OH)2(s) and the reduction of MnO4–(aq) to MnO2(s).
Answer:
See explanation
Explanation:
Oxidation half equation;
3Cd(s) + 6OH^-(aq) ------> 3Cd(OH)2(s) + 6e
Reduction half equation;
2MnO4^-(aq) + 8H^-(aq) + 6e --------> 2MnO2(s) + 4H2O(l)
Balanced reaction equation;
3Cd(s) + 6OH^-(aq) + 2MnO4^-(aq) + 8H^-(aq) ------> 3Cd(OH)2(s) + 2MnO2(s)
Number of electrons transferred = 6
Which of the following is an example of a physical property?*
the mass
ability to rust
flammability
ability to combust
Answer: The mass
Explanation: ability to rust, flammability, and ability to combust are chemical properties.
9. What happens to the cell outside of the nucleus when the virus has been copied so many times? a. The cell fights back b. The cell gets help from its neighbor cells C. The cell gets help from white blood cells d. The cell is destroyed
Answer: it think the answer is c.) The cell gets help from white blood cells or b.) The cell gets help from its neighbor cells.
Explanation:
How many molecules are in 3.01 g of H2O
A. 0.167 molecules
B. 54.18 molecules
C. 1.01x10^23 molecules
D. 6.022x10^23
Answer:
Option C
Explanation:
No. of Molecules=(Given Weight/Molar weight)*Avagadro No.
Given weight of H2O=3.01g
Molar weight of H2O=18g
On applying the formula, we get:
No. of Molecules=(3.01/18)*6.023*10²³=1.01*10²³
How many mL of a 6.0 M solution of HNO3 would be needed to prepare 300.0 mL of a 0.60 M solution of HNO3?
Answer:
500mL.
Explanation:
Which is the term for the different forms of a gene for a given trait?
Answer:
An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome. Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent.
Which is a characteristic of a physical change?
a
The chemical bonds in the substance are unchanged.
b
The change cannot be seen.
c
The molecules all move at the same speed.
d
The substance has reacted with another substance.
Mg(s) + HCl (l) --> H2 (g) +MgCl2 (s) A student conducted an experiment with 2g of magnesium and 3 mL of 6M hydrochloric acid. Equal volumes (3mL) of hydrochloric acid and magnesium strips (2g) were put into each tube. What are the reactants in this reaction?
Answer: Do you have an image so I can solve it?
The particles of a substance lose energy and change from
a disordered structure with large distances between the particles to
a loosely ordered state.
Which change of state is described?
Answer:
A Liquid
Explanation:
structure with large distance (gas) than goes to a loosely ordered state (liquid)
I hope this helps
Anyone know how to do this? It’s for Chemisty
Predict Will you find starch in a plant leaf grown in the light? Why?
Answer:
You would find starch in a plant leaf.
Explanation:
This is due to the fact that when there is excess energy, it will be stored in plant tissue as starch.
What are three main ocean currents?
3.4
Why is this cocktail not the perfect medication to treat infections by these
bacteria?
Answer:
many bacteria are resistant to penicillin and other β-lactam antibiotics - some bacteria have beta-lactamase enzymes and are able to break down the antibiotics - as a result, many drugs are combined with other drugs that are β-lactamase inhibitors.
Explanation:
Quizlet
What happens to the amount of carbon dioxide as the population increases?
Answer:
when population increases the amount of carbon dioxide also increases as population use oxygen and release carbon dioxide
Carbon dioxide is a major greenhouse gas. The increase in the population increases the carbon dioxide amount.
What is the relation between carbon and population?The main product released from the respiratory process of organisms, especially animals is carbon dioxide. The increase in their population will increase this product.
The increased population will increase the demand for the burning of fossil fuel, pollution, and respiration, and hence the product of these activities, carbon dioxide will increase in the atmosphere.
Therefore, the carbon dioxide will increase with an increase in the population.
Learn more about carbon dioxide and population here:
https://brainly.com/question/10153143
#SPJ2
Is combining ammonium chloride and water a physical or chemical change
If you have 35 moles of sodium hydroxide (NaOH) in a 5000 mL solution, what is the concentration of the NaOH in the solution?
Answer:
7 mol.dm^3
Explanation:
formula for calculating concentration: C = n/v
Start by changing 5000ml solution to dm^3 because volume is in dm^3
1 ml = 1cm^3
then from a cm^3 to dm^3 you divide by 1000
5000ml = 5000cm^3
5000÷1000= 5dm^3
c = n/v
= 35/5
= 7mol.dm^3
The amount of a solid substance that dissolves in a gas or in a liquid is affected by all of the following
except:
A- the nature of the substance
B- the temperature
C- the pressure
D- Stirring (Agitation)
Answer:
C. The Pressure
Explanation:
Pressure only affects the solubility of gases. It barely affects the solubility of solids and liquids.
Which ion dissociates in Acids?
A- ООН-
B- ОН+
C- ОН+
D- COOH
Characteristic orange light produced by sodium in a fl ame is due to an intense emission called the sodium D line, which is actually a doublet, with wavelengths (measured in vacuum) of 589.157 88 and 589.755 37 nm. The index of refraction of air at a wavelength near 589 nm is 1.000 292 6. Calculate the frequency, wavelength, and wavenumber of each component of the D line, measured in air.
Answer:
a. i. 5.092 × 10²⁰ Hz ii. 588.98554 nm ii. 10667809.11 rad/m
b. i. 5.087 × 10²⁰ Hz ii. 589.58286 nm iii. 10657001.3 rad/m
Explanation:
refractive index, n = λ/λ' where λ = wavelength in vacuum = and λ' = wavelength in air
a. For λ = 589.15788 nm,
i. Frequency,
f = c/λ where c = speed of light in vacuum = 3 × 10⁸ m/s and λ = 589.15788 nm = 589.15788 × 10⁻⁹ m
So, f = 3 × 10⁸ m/s ÷ 589.15788 × 10⁻⁹ m
= 0.005092 × 10¹⁷ /s
= 5.092 × 10²⁰ /s
= 5.092 × 10²⁰ Hz
ii. Wavelength,
Since n = λ/λ' where λ = wavelength in vacuum = and λ' = wavelength in air
and n = 1.0002926
λ' = λ/n
= 589.15788 nm/1.0002926
= 588.98554 nm
iii. Wave number, kk = 2π/λ'
= 2π/588.98554 nm
= 0.01066780911 rad/nm
= 0.01066780911 rad/nm × 10⁹ nm/1m
= 10667809.11 rad/m
b. For λ = 589.755 37 nm.,
i. Frequency,
f = c/λ where c = speed of light in vacuum = 3 × 10⁸ m/s and λ = 589.755 37 nm. = 589.755 37 × 10⁻⁹ m
So, f = 3 × 10⁸ m/s ÷ 589.755 37 × 10⁻⁹ m
= 0.005087 × 10¹⁷ /s
= 5.087 × 10²⁰ /s
= 5.087 × 10²⁰ Hz
ii. Wavelength,
Since n = λ/λ' where λ = wavelength in vacuum = and λ' = wavelength in air
and n = 1.0002926
λ' = λ/n
= 589.755 37 nm./1.0002926
= 589.58286 nm
iii. Wave number, kk = 2π/λ'
= 2π/589.58286 nm
= 0.0106570013 rad/nm
= 0.0106570013 rad/nm × 10⁹ nm/1m
= 10657001.3 rad/m
When a small piece of sodium metal is dropped into a beaker of water, hydrogen gas (H2) and a solution of sodium hydroxide (NaOH) are products. The solution becomes warm.
Answer:
The reaction is exothermic as the solution becomes warm.
Explanation:
Hello there!
In this case according to the described reaction between sodium metal and water, we can write up the chemical equation whereas the products turn out to be sodium hydroxide and hydrogen gas:
[tex]2Na+2H_2O\rightarrow 2NaOH+H_2[/tex]
Moreover, these reactions are known to be highly exothermic, for that reason the solution becomes warm as the reaction releases heat as it goes to completion.
Best regards!
Mass = 35g Volume = 7cm3 What is the Density?
Answer:
5 g/cm^3
Explanation:√3V=1.91293cm
6. List two (2) ethical issues that the healthcare provider has a public duty to report.
Answer: Communicable diseases, abuse gunshot wounds and forensic medicine
Explanation:
Weight is the measure of gravity on an object measured by a weight in Newtons. Weight changes if gravitational force changes.
Mass is the amount of kilogram in an object measured by a __________ in grams and does not change…it stays the _________.
Mass is an intrinsic property of matter and is measured in kilograms. The mass of a bird is a constant. A 15-gram bird is 15 grams, whether measured on the Earth, the Moon, or Mars. Weight is a measure ofthe force of gravity on a physical object and is measured in newtons.