A hypothetical element consists of 3 isotopeswith the following masses and natural abundances.
Isotopic Natural
Mass Abundance
Number %
1 39 78.8
2 40 18.1
3 41 3.1
what is the atomic weight
Answers
39 x .788 = 30.732
40 x .181 = 5.43
41 x .031 =+ 1.24
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39 since there are only 2 significant figures given for each mass
Final answer:
The atomic weight of a hypothetical element with isotopes of masses 39, 40, and 41 and natural abundances of 78.8%, 18.1%, and 3.1% respectively, is approximately 39.243 atomic mass units (amu).
Explanation:
To calculate the atomic weight of an element from its isotopes' masses and abundances, use the formula: atomic weight = (mass1 x abundance1) + (mass2 x abundance2) + ... (massn x abundancen), where the masses are the isotopes' masses and the abundances are given as proportions (i.e., percentages divided by 100).
Using the values from your question, the calculation would be as follows:
Atomic weight = (39 x 0.788) + (40 x 0.181) + (41 x 0.031) = 30.732 + 7.24 + 1.271 = 39.243. So, the atomic weight of the hypothetical element is approximately 39.243 atomic mass units (amu).
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Related Questions
What volume is occupied by 18.4 g oxygen at 28.0°C and a pressure of 0.998 torr? (round to sig figs)
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Is an isotope more or less stable the longer the half life?
b. Carbon, atomic number 6
c. Neon, atomic number 10
d. Fluorine, atomic number 9
Answers
Answer:
Neon, atomic number 10, is stable.
Explanation:
Valencia electrons are the electrons found in the last electronic layer (called valence orbitals). These electrons are what determine the ability of the atom to form bonds. When an element joins another, it does so through its valence electrons.
The noble gases include the elements of group 18 of the periodic table. The noble gases are characterized by their very low chemical reactivity because they are very stable. This is because they have the full valence layer (complying with the octet rule, that is, they have 8 electrons at their last energy level, with the exception of helium that has 2 electrons), causing them to have a low tendency to capture or release electrons . That is why they are also called inert gases.
The Neon, whose atomic number is 10, belongs to the group of noble gases. So this element is stable.
Neon is the most stable because it has 8 valence electrons. when an element has full number of valence electrons, they become stable.
Answers
yours only had carbon dioxide and no h2o
therefore it is wrong
(2) H2O2 (4) OH–
Answers
Answer: Option (3) is the correct answer.
Explanation:
In an aqueous solution, a compound exists in the form of ions that is in the form of protons and electrons.
Protons are positively charged and electrons are negatively charged. A proton (usually hydrogen ion, ) in water (solvent) also exists as
.
For example,
This shows that the conjugate acid of is
.
Thus, we can conclude that a hydrogen ion, H+, in aqueous solution may also be written as .
c. atomic numbers
b. chemical behavior
d. mass numbers
Answers
Answer:
d. mass numbers
Explanation:
Isotopes are atoms that have the same number of protons (atomic number) but different number of neutrons. As the definition of mass number is the sum of protons and neutron in an atom, the isotopes have different mass numbers.
It can be reshaped by a force.
It ignites at high temperatures.
It can combine with oxygen.
Answers
Answer is: It can be reshaped by a force.
Physical property can be observed and measured without any changes in molecular composition. The same substance is present before and after the change, changing the shape is physical change.
Copper reaction with acid, ignition and combination with oxygen are chemical change (chemical reaction), because new substances are formed, the atoms are rearranged and the reaction is followed by an energy change.
That is because physical properties are ones that don't change the substance when it is physically altered. If copper is physically changed, none of its other chemical properties are influenced.
Answers
Answer:
To calculate the volume of the approximately 0.014 M copper (II) sulfate solution needed to prepare 100.00 milliliters of a 0.00028 M copper (II) sulfate solution, you can use the formula:
(Volume 1)(Concentration 1) = (Volume 2)(Concentration 2)
So, rearranging the formula, you can solve for Volume 1 (the volume of the 0.014 M solution):
Volume 1 = (Volume 2)(Concentration 2) / Concentration 1
Plugging in the values:
Volume 1 = (100.00 milliliters)(0.00028 M) / 0.014 M
Volume 1 ≈ 2.00 milliliters
Approximately 2.00 milliliters of the approximately 0.014 M copper (II) sulfate solution are needed to prepare 100.00 milliliters of a 0.00028 M copper (II) sulfate solution.