If an least one neutron from U-235 fission<span> strikes another nucleus and causes it to fission, then the chain reaction will continue. If the reaction will sustain itself, it is said to be "critical", and the mass of U-235 required to produced the critical condition is said to be a "</span>critical mass<span>". A critical chain reaction can be achieved at low concentrations of U-235 if the neutrons from fission are </span>moderated to lower their speed, since the probability for fission with slow neutrons is greater. <span>A fission chain reaction produces intermediate mass </span>fragments<span> which are highly </span>radioactive<span> and produce further energy by their radioactive decay. Some of them produce neutrons, called </span>delayed neutrons<span>, which contribute to the fission chain reaction.
Hope this helps you..</span>
The answer is C. No all cells have cell walls. Prokaryotes don’t have a nucleus or chloroplast. Leaving C to be correct
Explanation:
1 mole of a gas has 22.4 L of volume at STP. Therefore, 0.5 mol of H2 has 0.5 x 6.022 x 1023 = 3.011 x 1023 molecules. Hence, the number of moles, molecules and atoms present in 11.2 liters of H2 at STP are 0.5 , 3.011 x 1023 and 6.022 x 1023 respectively.