After 25 days, it remains radon 5.9x10^5 atoms.
Half-life is the time required for a quantity (in this example number of radioactive radon) to reduce to half its initial value.
N(Ra) = 5.7×10^7; initial number of radon atoms
t1/2(Ra) = 3.8 days; the half-life of the radon is 3.8 days
n = 25 days / 3.8 days
n = 6.58; number of half-lifes of radon
N1(Ra) = N(Ra) x (1/2)^n
N1(Ra) = 5.7×10^7 x (1/2)^6.58
N1(Ra) = 5.9x10^5; number of radon atoms after 25 days
The half-life is independent of initial concentration (size of the sample).
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Hydrogen exhibit similar properties with lithium because both are in the same group 1 as they both have a valence electron of 1
- Hydrogen also exhibit some similar properties with fluorine simply because they are both non metals
<h3>What is an element?</h3>
An element is a substance which cannot be split into simpler forms by an ordinary chemical process. This simply goes to say that elements are substances which cannot be decomposed into simpler substances by ordinary chemical reactions.
An atom is the smallest unit or part of an element which can take part in a chemical reaction.
On a general note, elements are classified as thus:
- Metals, non-metal, and metalloid.
- The extreme left side elements in the periodic table are metals, for example, aluminum, sodium, calcium, caesium, etc.
- However, elements on the right side are generally referred to as non-metals, carbon, chlorine, oxygen,
So therefore, hydrogen exhibit similar properties with lithium because both are in the same group 1 as they both have a valence electron of 1
- Hydrogen also exhibit some similar properties with fluorine simply because they are both non metals
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Answer:
0.571 mol
Explanation:
Given data:
Number of moles of NaHCO₃ = 0.571 mol
Number of moles of CO₂ produced = ?
Solution:
Chemical equation:
NaHCO₃ + C₃H₆O₃ → CO₂ + C₃H₅NaO₃ + H₂O
Now we will compare the moles of CO₂ with NaHCO₃ from balance chemical equation.
NaHCO₃ : CO₂
1 : 1
0.571 : 0.571
So number of moles of CO₂ produced are 0.571.
Reactivity - Reactivity refers to how likely or vigorously an atom is to react with other substances. This is usually determined by how easily electrons can be removed (ionization energy) and how badly they want to take other atom's electrons (electronegativity) because it is the transfer/interaction of electrons that is the basis of chemical reactions.
Metals
Period - reactivity decreases as you go from left to right across a period.
Group - reactivity increases as you go down a group
Why? The farther to the left and down the periodic chart you go, the easier it is for electrons to be given or taken away, resulting in higher reactivity.
Non-metals
Period - reactivity increases as you go from the left to the right across a period.
Group - reactivity decreases as you go down the group.
Why? The farther right and up you go on the periodic table, the higher the electronegativity, resulting in a more vigorous exchange of electron