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Atomic Mass
Atomic mass is the mass of protons, neutrons, and electrons in a single specific atom.
1,752 Questions
Why is boron's atomic mass 10.82 and not 11?
Boron has two naturally occurring isotopes, boron-10 and boron-11. The atomic mass of 10.82 arises from the weighted average of the isotopic masses and their abundances in a sample of boron found in nature. Boron-10 is more abundant than boron-11, causing the average atomic mass to be closer to 10.82 than 11.
How many atomic mass do krypton have?
47 neutron and 36 proton and 36 electron because its atomic number is 36.
The atomic mass is calculated by averaging the masses of the isotopes based on their abundance. In this case, 75% of the isotopes have a mass of 35.0 amu and 25% have a mass of 37.0 amu.
Atomic mass = (0.75 * 35.0 amu) + (0.25 * 37.0 amu) = 35.5 amu.
The molar mass of cesium (Cs) is approximately 133 g/mol. Therefore, the mass of 3.00 mol of cesium would be 3.00 mol x 133 g/mol = 399 g.
If the atomic mass of a carbon is 12 amu 1 mole of pure carbon will have a mass of?
1 mole of carbon atoms will have a mass of 12 grams (atomic mass in amu is numerically equivalent to the molar mass in grams per mole).
What is the formula mass of nitrogen monoxide in atomic mass units?
The formula mass of nitrogen monoxide (NO) is calculated by adding the atomic masses of nitrogen (N) and oxygen (O). The atomic mass of nitrogen is approximately 14 atomic mass units (amu) and the atomic mass of oxygen is approximately 16 amu. Therefore, the formula mass of NO is 14 + 16 = 30 amu.
Cobalt and Nickel are the two elements from the first 20 elements of the periodic table that are not arranged in order of increasing atomic mass. This is due to the placement of cobalt with a slightly lower atomic mass compared to nickel, which occurs due to the meticulous arrangement of elements based on their chemical properties and not just atomic masses.
To convert mass to atoms:
Find the atomic mass of the element in the substance. You can find atomic masses on the periodic table. Ex. Lithium's atomic mass is 6.9 grams (round if you need to)
Then find the mass of the substance in grams. Ex. you have 18.2 grams of a sample of Lithium.
The mass of the sample is multiplied by 6.02 * 1023 and divided by the atomic mass.
Ex.
mass of sample in grams * (6.02 * 1023 atoms) / (atomic mass) = # atoms in grams
18.2 grams * (6.02 * 1023 atoms) / (6.9 grams) = 1.59* 1024 atoms
The number 6.02 * 1023 is Avogadro's Constant which is the amount of atoms (or molecules) in one mole.
How do you calculate the atomic mass of bromine?
To calculate the atomic mass of bromine, you would take the weighted average of the isotopic masses of bromine's isotopes, considering their relative abundance in nature. The atomic mass of bromine is approximately 79.904 u.
One atomic mass unit equals 931 MeV?
No, one atomic mass unit is equal to 931.5 MeV (mega-electron volts). This value is obtained by converting the mass-energy equivalence relationship (E = mc^2) where 1 atomic mass unit is equivalent to 931.5 MeV.
The atomic mass of Cu-63 is expressed to what number of significant figures?
The atomic mass of Cu-63 should be expressed to two significant figures, which are 63.
Why do you calculate the number of electrons by the atomic mass and number?
You calculate the number of electrons by the atomic mass and number because elements have the same number of electrons as they do protons. The atomic number tells you the number of protons, which is also the number of electrons in a neutral atom. By using the atomic mass to find the number of neutrons, you can determine the overall charge and number of electrons in an atom.
What is the atomic mass of neon'?
The approximate mass is 11.
Technically you could express this in units of daltons as 11 Da (Daltons previously called amu, Atomic Mass unit, or as 11 (the dimensionless, relative atomic mass which chemists simply call atomic weight) .
Atomic Mass and Atomic Number of neon?
The Atomic number of Neon is 10 and the Atomic weight is about 20.18g rounded off to 2 decimal places.
If you don't have a periodic table you should get one most periodic tables have the atomic weight of all elements you need to know to around 2 decimals. I printed mine off Google images =)
For the simple reason that the most common isotope doesn't make up 100% of the element. If you use just that mass, your calculations will be off by anywhere from 0.5% to 3%. That doesn't sound like much, but when you are dealing with huge commodities of dangerous chemicals that need to be in the exactly specified mix or creating drugs that require a precise value of medication to prevent under- or overdosage, you had better be closer than 0.5%.
the mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.
What is the formula mass of nitrogen monoxide in atomic mass?
The formula mass of a compound is the sum of the atomic masses of all the atoms in the chemical formula. For nitrogen monoxide, the chemical formula is NO. The atomic mass of nitrogen (N) is approximately 14.01 g/mol, and for oxygen (O) is approximately 16 g/mol. Therefore, the formula mass of nitrogen monoxide (NO) is approximately 14.01 + 16 = 30.01 g/mol.
Which element or elements have an atomic mass between 15 and 19?
Oxygen (15.9994)
Flourine (18.9984032)
What is the atomic mass in Hindi?
The atomic mass (ma) is the mass of a specific isotope, most often expressed in unified atomic mass units.[1] The atomic mass is the total mass of protons, neutrons and electrons in a single atom.[2]
The atomic mass is sometimes incorrectly used as a synonym of relative atomic mass, average atomic mass and atomic weight; these differ subtly from the atomic mass. The atomic mass is defined as the mass of an atom, which can only be one isotope at a time and is not an abundance-weighted average as in the case of atomic weight. In the case of many elements that have one dominant isotope the actual numerical similarity/difference between the atomic mass of the most common isotope and the relative atomic mass or standard atomic weights can be very small such that it does not affect most bulk calculations-but such an error can be critical when considering individual atoms. For elements with more than one common isotope the difference even to the most common atomic mass can be half a mass unit or more (e.g. chlorine). The atomic mass of an uncommon isotope can differ from the relative atomic mass or standard atomic weight by several mass units.
How does the nuclear radius vary with atomic mass number?
The nuclear radius R is related to the mass number A as follows:
R=RoA1/3,where Ro =constant=(1.2 to 1.7) x 10 -15
Thus nuclear radius varies as A1/3
Why does beryllium have an atomic mass of 9.01 instead of 9?
There are two main reasons why an element has an atomic mass that is non-integral.
The first reason is that naturally occurring elements often consist of more than one isotope, and the mass given is actually the average mass. A common example is Chlorine, which has two isotopes, 35Cl and 37Cl, in a 3:1 ratio and the average mass ends up at around 35.5.
The other reason is a little more complex. The mass of an atom comprises the sum of the mass of the neutrons, the protons, the electrons and the nuclear binding energy.
For simplicity, let us look at the mass of helium and use the old system where hydrogen has a defined mass of 1.000. You might think that helium (two protons, two neutrons, two electrons) would have a mass of exactly 4.000. However:
1. The mass of a hydrogen atom is the sum of 1 proton + 1 electron. A helium atom has twice this plus two neutrons
2. The mass of a proton, or that of a proton plus an electron, is different from the mass of a neutron.
3. When hydrogen/deuterium/tritium atoms combine to form helium atoms, energy is given out, and enough energy is given out that the equivalence of mass and energy (calculated through E=mc2) results in a significant loss of mass from the final atom.
In combination, these results mean that the mass of one atom is never a simple multiple of another, so with the exception of the atom that we actually define as having a specific mass (as we currently define oxygen to have a mass of 16.0000 amu), no atom will never have an integral mass.
In the case of Beryllium, the mass of 9Be is not exactly 9.0000, plus there are trace amounts of 10Be in naturally occurring samples that take the average mass up to a fraction over 9.00.
What is the atomic mass when there are 45 neutrons and 35 electrons?
The atomic mass of an element is determined by the sum of its protons and neutrons. If an atom has 45 neutrons, the atomic mass would be the sum of the number of protons and neutrons, assuming neutral charge. Since the number of protons is not provided, the atomic mass cannot be determined with the information given.
Which of the atomic particles have a mass that is 1836 times smaller than one atomic mass unit?
Electrons have a mass that is approximately 1836 times smaller than one atomic mass unit. Electrons are fundamental particles with a mass of about 9.1 x 10^-31 kilograms, which is considered negligible compared to the mass of protons and neutrons.
Which one particle has a mass of approximately atomic mass unit and a unit positive charge?
none of the particles are 1g. (g stands for gram which is about the weight of a small paperclip.) however the proton has a positive charge.
How many neutrons are does yttrium have with an atomic number of 39 and atomic mass of 89?
Yttrium has 50 neutrons. To find the number of neutrons, subtract the atomic number (39) from the atomic mass (89): 89 - 39 = 50 neutrons.
