CH4 + 2 O2 ---> CO2 + 2 H2O Q = 891,6 kJ / mol CH4
1 mol CH4 = 16 g
16 g ---- 891,6 kJ
x g ----- 272 kJ
x = 272 kJ × 16 g / 891,6 kJ = 4,88 g
You must burn 4,88 g of CH4.
:-) ;-)
Answer:
<em>Option A. It was delivered by comets that crashed into Earth's surface.</em>
Explanation:
<em><u>Uranium (U) is a chemical element with atomic number 92.</u></em>
<em />
<em>For many years, a large number of scientists have been studying the abundance and origin of the isotopes of uranium in Earth</em>. <u>According to some theories, the Earth's uranium was produced in one or more supernovae</u> (an explosive brightening of a star), in wich, the main process consists in the rapid capture of neutrons by seed nuclei at great rates. <u>Another theory proposes that uranium is created during the merger of two neutron stars</u> (neutron stars are very dense), because, when such dense bodies come closer together the gravitational force cause them to merge, producing huge amounts of hevy metals like uranium.
<u><em>Many analyses have been made of the uranium in rocks of the Earth. These measurements shows that the abundance of uranium is bigger in the crust and upper mantle of the Earth</em></u>.
So, knowing that Earth's uranium was produced through one of these processes, <u><em>the best answer is option A, the uranium was delivered by comets that crashed into Earth's surface.</em></u>
Have a nice day!
Answer:
Volume = 30cm³
Explanation:
A block is a geometrical figure and its volume, -look at the figure-, follows the equation:
Volume = Width*Length*Height
As the measurements of the block are 5.00cm, 3.00cm and 2.00cm, the volume is:
Volume = 5.00cm*2.00cm*3.00cm
<h3>Volume = 30cm³</h3>
Answer:
C.
Explanation:
We get it from the food we eat by mixing it with fluids. Also, you can always look up the answer.
Hope this helps! :) Plz mark as brainliest!
Potassium carbonate<span> (K</span>2CO3<span>) is a white salt, </span>soluble in water<span> (</span>insoluble<span> in ethanol) which forms a strongly alkaline solution. </span>
