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2021-06-17

How do you find the half-life?

How do you find the half-life?

half-life = ln (2) / (decay constant). To measure the decay constant, we take a sample of known mass and measure the number of radioactive decays per second as a function of time.

How do you define half-life?

Half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive …

How many years is a half-life?

A radioactive half-life refers to the amount of time it takes for half of the original isotope to decay. For example, if the half-life of a 50.0 gram sample is 3 years, then in 3 years only 25 grams would remain. During the next 3 years, 12.5 grams would remain and so on.

Why do we measure Half-Life?

We use the half-life because radioactive decay is a matter of chance. When one atom will decay is anyone’s guess. If you have two identical atoms, one could decay immediately, the other could hang around for a century or a millenium. We use the half-life because radioactive decay is a matter of chance.

What element has the shortest half life?

Uranium-234

What element has longest half life?

xenon-124

What is the heaviest isotope?

uranium

What’s the heaviest mineral on Earth?

Osmium is one of the heaviest materials on earth, weighing twice as much as lead per teaspoon. Osmium is a chemical element in the platinum group metals; it’s often used as alloys in electrical contacts and fountain pen nibs.

How do you know which isotope is heavier?

To determine the most abundant isotopic form of an element, compare given isotopes to the weighted average on the periodic table. For example, the three hydrogen isotopes (shown above) are H-1, H-2, and H-3. The atomic mass or weighted average of hydrogen is around 1.008 amu ( look again to the periodic table).

Is magnesium stable?

At normal temperatures it is stable in air and water because of the formation of a thin protective skin of oxide, but it is attacked by steam. Magnesium is a powerful reducing agent and is used to produce other metals from their compounds (e.g., titanium, zirconium, and hafnium). It reacts directly with many elements.

Does magnesium oxidize in air?

It tarnishes slightly when exposed to air, although, unlike the heavier alkaline earth metals, an oxygen-free environment is unnecessary for storage because magnesium is protected by a thin layer of oxide that is fairly impermeable and difficult to remove.

How fast does magnesium corrode?

The protection supplied by this film is therefore highly dependent on the condition of exposure. High purity magnesium is reported to have a corrosion rate of 10-2-10-3 mils per year (mpy) when exposed to 2 normal KOH solutions at 25 °C [3].

How can you prevent magnesium from corroding?

Corrosion Protection by Cold Spray The presence of aluminum on the surface has been shown to reduce the general and galvanic corrosion tendency of magnesium components (see Figure 5a).

Does magnesium corrodes faster than iron?

Magnesium is more reactive than iron. It oxidises more readily than iron so the nail does not rust. Iron is more reactive than copper. This means it oxidises more readily than copper, so it rusts faster than the nail alone.