Perhaps when they are trying to find the distance of an asteroid to the Earth to find out whether or not it is a hazard to Earth.
Chemistry is the study of substances—that is, elements and compounds.
Answer:
13.53 kJ
Explanation:
The energy of a gas can be calculated by the equation:
E = (3/2)*n*R*T
Where n is the number of moles, R is the gas constant (8.314 J/mol.K), and T is the temperature.
E = (3/2)*3.5*8.314*310
E = 13,531.035 J
E = 13.53 kJ
Answer:
A)21
Explanation:
To know the difference between the number of electrons in the two atoms, we must first know the number of electrons in the atoms.
For Selenium, Se, we have 34 electrons. The element is in group 6 on the periodic table.
Aluminum on the other hand is in the Boron family with a total of 13 electrons.
The difference,( 34-13) electrons gives a total of 21 electrons
According to the balanced chemical equation:
4 HPO₃ + 12 C → 2 H₂ + 12 CO + P₄
4 moles of HPO₃ ---gives---> 12 moles of CO
2.73 moles of HPO₃ ---gives---> ? moles of CO
so number of moles of CO =

= 8.19 moles of CO
Number of molecules of CO = number of moles * Avogadro's number
= 8.19 * (6.022 * 10²³) = 4.93 * 10²⁴ molecules