Answer:
Lead
Explanation:
Lead (Pb) has atomic number 82
Ex Polonium (Po) has atomic number 84 and mass number 212
Answer:
1.53x10^22 atoms of Au
Explanation:
To find the atoms of gold we need first, to convert the mass of gold to moles using molar mass of gold (196.97g/mol). Then, these moles must be converted to number of atoms based on definition of moles (1 mole = 6.022x10²³ atoms).
<em>Moles Au:</em>
5.00g Au * (1mol / 196.97g) = 0.0254 moles of Au
<em>Atoms of Au:</em>
0.0254 moles * (6.022x10²³ atoms / 1 mole) =
<h3>1.53x10^22 atoms of Au</h3>
How many grams Carbon in 1 moles? The answer is 12.0107.
<span>We assume you are converting between </span>grams Carbon<span> and </span>mole.
You can view more details on each measurement unit:
molecular weight of Carbon<span> or </span>moles
<span>The molecular formula for Carbon is </span>C.
<span>The SI base unit for </span>amount of substance<span> is the mole.</span>
1 grams Carbon is equal to 0.0832590939745 mole.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between grams Carbon and mole.
<span>Type in your own numbers in the form to convert the units!
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Answer:
1. Exothermic.
2. -1598 kJ.
Explanation:
Hello!
1. In this case, according to the reaction, we can infer that 799 kJ of energy are evolved (given off, released) it means that the enthalpy of reaction is negative as the reactants have more energy than the products; which means this is an exothermic reaction.
2. Here, as we know that the enthalpy of reaction is -799 kJ/mol, we can compute the q-value as shown below, considering the reacted 2 moles of solid iron:

Which means that 1598 kJ of energy are evolved when 2 moles of solid iron react.
Best regards!
There are 137 atoms in this molecule. C55 + H72 = 127. 127 + Mg (one atom of magnesium = 128. 128 + N4 = 132. 132 + O5 = 137.