Courtney’s in minerals can vary due to impurities but is usually diagnostic we determine the relative hardness of minerals using a scale diversity bye mineralogists Freidrich Mohs The scale assigned hardness Tuten common index minerals and is based up on the ability of one mineral to scratch another
Answer:
4 significant figures
Explanation:
Significant figures are the units/digits within a number that make the number more accurate and precise.
All digits (except for 0) are always significant. Therefore, all the digits in 43.55 are significant. Since there are 4 digits in the given number, there are 4 significant figures.
1. A heavy nucleus (U235 or Pu239), when bombarded by slow moving neutrons, split into two
or more nuclei.
2. Two or more neutrons are produced by fission of each nucleus.
3. Huge amount of energy is produced as a result of nuclear fission.
4. All the fission fragments are radioactive, giving off β and radiations.
<span>5. The atomic weights of fission products range from about </span>70 to 160.
6. The nuclear chain reactions can be controlled and maintained steadily by absorbing a
desired number of neutrons. This process is used in nuclear reactor.
<span>7. All the fission reactions are self-propagating chain-reactions because fission products contain </span>
neutrons (secondary neutrons) which further cause fission in other nuclei.
8. Every secondary neutron, released in the fission process, does not strike a nucleus, some
escape into air and hence a chain reaction cannot be maintained.
<span>9. The number of neutrons, resulting from a single fission, is known as the multiplication factor. </span>
When the multiplication factor is less than 1, a chain reaction does not take place.
<span>10. The control of chain reaction is necessary in order to maintain a steady reaction. This is </span>
carried out by absorbing a desired number of neutron by employing materials like
percentage of Cd, B or steel.
11. In a nuclear reactor, the multifactor is one. This is achieved by proper arrangement of
<span>fissionable materials.</span>
<span>The pressure of nitrogen in atmospheres of a sample that is at 745 mmHg-
n2= .780 atm because
78 (from the 78%)
78/100=0.78.</span>
Answer : The final pressure will be, 666.2 mmHg
Explanation :
Boyle's Law : It is defined as the pressure of the gas is inversely proportional to the volume of the gas at constant temperature and number of moles.
or,
where,
= initial pressure = 790 mmHg
= final pressure = ?
= initial volume = 101.2 mL
= final volume = 120 mL
Now put all the given values in the above equation, we get:
Therefore, the final pressure will be, 666.2 mmHg
