The top left corner shows the atomic number which is 3.
Answer:
Percentage of copper = 88%
Explanation:
Given data:
Mass of copper = 51.2 g
Mass of tin = 6.84 g
Percentage of copper = ?
Solution:
Formula:
Percentage of copper = mass of copper / total mass × 100
Now we will determine the total mass:
Total mass = mass of copper + mass of tin
Total mass = 51.2 g + 6.84 g
Total mass = 58.04 g
Now we will calculate the percentage of copper.
Percentage of copper = 51.2 g / 58.04 g × 100
Percentage of copper = 0.88 × 100
Percentage of copper = 88%
KI-starch paper allows the detection of strong oxidizers such as nitrite. It is used here to control diazotization of 4-nitroaniline. Nitrite oxidizes potassium iodide in order to form elemental iodine which reacts with starch to a blue-violet complex. With KI-starch paper, enough sodium nitrite is added to produce nitrous acid, which <span>then will react with 4-nitroaniline to form a diazonium salt.</span>
