Answer:
Yes, Mass Extinctions May Have Been Caused By Meteors, as the probability of mass extinction occurring after an asteroid that could hit a random location on the Earth's surface was approximately 13% when the Chicxulub-scale asteroid hit the Earth.
Soot could be the main cause of mass extinction after an asteroid impact.
Answer:
45 g of the solid Tris will be dissolved in 2.5 liters of water.
Explanation:
Recall that:
<em>Number of moles = molarity x volume</em>
Hence, number of moles of Tris present in 2.5 liters, 150 mM solution:
= 150/1000 x 2.5 = 0.375 moles
Also, recall that:
<em>No of moles of substance = mass/molar mass.</em>
Hence, mass of 0.375 moles substance:
= no of moles of the substance x molar mass of the substance.
= 0.375 x 120 = 45 g.
Therefore, in order to prepare 2.5 liters, 150 mM of an aqueous solution of Tris, 45 g of the solid Tris will be dissolved in 2.5 liters of water.
Salinity matters more than depth or density
Nitrogen is from the atmosphere is converted into nitrates by nitrogen fixing bacteria such as rhizobium which is found in the root nodules of leguminous crops
