The answer is D) 144 grams O2
Explanation:
4. limestone heat lime + carbon dioxide
The reactants in this expression above is limestone
The products of the reaction is carbon dioxide and lime
Reactant is the species that gives the product and it is usually found on the left hand side of the expression.
The product is the substance on the right hand side of the expression that forms through the experiment.
Heat is used to facilitate the reaction.
5. An exothermic reaction is a reaction in which heat is given off.
An endothermic reaction is a reaction in which heat is absorbed in the process.
An exothermic reaction is always warmer after the reaction whereas an endothermic reaction is colder at the end of the reaction.
Each natural element has a characteristic light spectrum that helps identify it in samples of unknown substances. Spectroscopy is the practice of examining spectra and comparing them to those of known elements. Using spectroscopy methods, scientists can identify pure substances or compounds and the elements in them.
The initial temperature of the gold was 84 K.
<em>Step 1</em>. Calculate the <em>temperature change</em>.
The formula for the heat (<em>q</em>) absorbed is
<em>q</em> = <em>mC</em>Δ<em>T
</em>
We can solve this equation to get
Δ<em>T</em> = <em>q</em>/(<em>m</em>C)
<em>q</em> = 12 000 J; <em>m</em> = 800 g; <em>C</em> = 0.129 J·K⁻¹g⁻¹
∴ Δ<em>T</em> = 12 000 J/(800 g × 0.129 J·K⁻¹g⁻¹) = 116 K
<em>Step </em>2. Calculate the <em>initial temperature
</em>
Δ<em>T</em> = <em>T</em>_f – <em>T</em>_i = 200 K – <em>T</em>_i = 116 K
<em>T</em>_i = 200 K – 116 K = 84 K
