The specific activity (in Ci/g) if 1.65 mg of an isotope emits 1.56X10⁶α a particles per second.
<h3>What is isotope?</h3>
Isotopes are two or more types of atoms with the same atomic number (number of protons in their nuclei) and periodic table position (and so belong to the same chemical element), but distinct nucleon numbers due to differing numbers of neutrons in their nuclei. While all isotopes of a given element have nearly identical chemical properties, their atomic weights and physical properties differ.
The term isotope is derived from the Greek roots isos and topos, which means that different isotopes of the same element occupy the same position on the periodic table. Margaret Todd, a Scottish doctor and writer, coined the phrase in 1913 as a recommendation to British chemist Frederick Soddy.
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The molar mass of NO₂ is 46.0 g/mol
The molar mass of Pb (NO₃)₂ is 331.2 g/mol
First there is a need to find the number of moles of NO₂ via the stoichiometry of reaction:
2Pb(NO₃)₂ → 2PbO (s) + 4NO₂ (g) + 02 (g)
2 × 331.2 g = 4 × 46.0 g
16.87 g = x (mass of NO₂)
mass of NO₂ = 16.87 × 4 × 46 / 2 × 331.2
mass of NO₂ = 3104.08 / 662.4
mass of NO₂ = 4.686 g of NO₂
Now the number of moles are:
1 mole NO₂ = 46.0 g
x moles of NO₂ = 4.686 g
4.686 × 1 / 46.0 = 0.101 moles of NO₂
1 mole = 22.4 L (at STP)
0.101 moles of NO₂ = 0.101 × 22.4 / 1
= 2.26 L
Find a periodic table of elements.<span> This is a color-coded table made up of many different squares that lists all of the chemical elements known to humankind. The periodic table reveals lots of information about the elements — we'll use some of this information to determine the number of valence electrons in the atom we're investigating. You can usually find these inside the cover of chemistry textbooks. There is also an excellent interactive table available online </span>here<span>.</span>
I can not answer the question without the answer choices, when it is put up i will be able to answer the question.
V2O5 is the formula. Vanadium has a charge of +5 and oxygen is -2, so to make them equal, you need to double the vanadium charge and multiply the oxygen charge by 5