Table of Contents
What is the SI unit for radioactivity?
becquerel
The becquerel (symbol: Bq) is the SI unit of radioactivity and is defined as one nuclear disintegration per second 1; it officially replaced the curie (Ci), the unit in the superseded cgs system, in 1975.
Is curie SI unit of radioactivity?
The curie (symbol Ci) is a non-SI unit of radioactivity originally defined in 1910. In 1975 the General Conference on Weights and Measures gave the becquerel (Bq), defined as one nuclear decay per second, official status as the SI unit of activity.
How many disintegrations per second does a curie have?
37 billion
As such, 1 Ci is equal to 37 billion (3.7 x 1010) disintegrations per second, so 1 Ci also equals 37 billion (3.7 x 1010) Bequerels (Bq). A curie is also a quantity of any radionuclide that decays at a rate of 37 billion disintegrations per second (1 gram of radium, for example).
What are the units of half-life?
Half-life units in ‘years’ & ‘seconds’ are the most widely used, but actually, whatever you wish sec, min, hrs, days, yrs. The application and one’s preference could dictate more appropriate units.
What is activity and its unit?
A measure of radioactivity (activity) is based on counting of disintegrations per second. The SI unit of activity is the becquerel (Bq), equal to one reciprocal second.
How many curies of radiation is safe?
Adult: 5,000 Millirems. The current federal occupational limit of exposure per year for an adult (the limit for a worker using radiation) is “as low as reasonably achievable; however, not to exceed 5,000 millirems” above the 300+ millirems of natural sources of radiation and any medical radiation.
What is the value of one curie?
One curie (1 Ci) is equal to 3.7 × 1010 radioactive decays per second, which is roughly the amount of decays that occur in 1 gram of radium per second and is 3.7 × 1010 becquerels (Bq). In 1975 the becquerel replaced the curie as the official radiation unit in the International System of Units (SI).
How many millionaires are in a Curie?
So, a millicurie (mCi) is . 001 curie. A microcurie (µCi) is . 000001 curie.
What are the units of the Arrhenius equation?
In both forms of the equation, the units of A are the same as those of the rate constant. The units vary according to the order of the reaction. In a first-order reaction, A has units of per second (s-1), so it may also be called the frequency factor.
How to find the slope of the Arrhenius equation?
The value of the slope (m) is equal to -Ea/R where R is a constant equal to 8.314 J/mol-K. “Two-Point Form” of the Arrhenius Equation The activation energy can also be found algebraically by substituting two rate constants (k 1 , k 2 ) and the two corresponding reaction temperatures (T 1 , T 2 ) into the Arrhenius Equation (2) .
When is the Arrhenius equation plotted on the x axis?
When the logarithm of the rate constant (ln K) is plotted on the Y-axis and the inverse of the absolute temperature (1/T) is plotted on the X-axis, the resulting graph is called an Arrhenius plot. The Arrhenius plot for the decomposition of nitrogen dioxide is illustrated above. Does the Arrhenius Equation Account for Catalysts?
How did Arrhenius calculate the activation energy of reactants?
Arrhenius argued that for reactants to transform into products, they must first acquire a minimum amount of energy, called the activation energy E a. At an absolute temperature T, the fraction of molecules that have a kinetic energy greater than E a can be calculated from statistical mechanics.