Answer:
If the half-life of 14C is 5730 years, when this period of time has passed it will have been halved, it is called the exponential decay law of radioactive isotopes.
Answer:
H2O> NH3> CH4
Explanation:
According to valence shell electron pair repulsion theory (VSEPR), bond angles and repulsion of electron pairs depends on the nature of electron pairs on the central atom of the molecule. Lone pairs cause more repulsion (and distortion of bond angles) than bond pairs). Lone pair- lone pair repulsion is greater than lone pair bond pair repulsion.
Water contains two lone pairs on oxygen hence it experiences the greatest repulsion. Ammonia has only one lone pair on nitrogen hence there is lesser repulsion between lone pairs and bond pairs. Methane possess only bond pairs of electrons hence it has the least repulsion.
The most common pH indicator used in Simmons Citrate Agar is Bromthymol Blue (BTB)
Simmons Citrate Agar is a selective and differential medium used for the detection and differentiation of Enterobacteriaceae (gram-negative bacteria).
The medium contains sodium citrate as the sole carbon source, which is used to differentiate organisms based on their ability to utilize citrate as a sole carbon source.
The medium also contains pH indicators that change color based on the pH of the medium. The most common pH indicator used in Simmons Citrate Agar is Bromthymol Blue (BTB).
BTB is a pH indicator that turns yellow in acidic conditions and blue in basic conditions. As the bacteria metabolize the citrate in the medium, they produce acids, which cause the medium to become acidic.
This change in pH is detected by the BTB, which changes color from blue to yellow. The yellow coloration of the medium is an indication that the organism is utilizing citrate as a sole carbon source.
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A balance in a lab measures the weight of a substance or object.
Weight is the mass of the body x the gravitation pull on the mass of the object.
So the mass of the object can be found by dividing the weight by gravitational constant.
The gravitational constant on earth is 1. so if a balance says that a substance weighs 300g then its mass is also 300g on earth because 300/1 = 300.
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