The right answer for the question that is being asked and shown above is that: "<span>2)A gas forms, and there is a change of color. " </span>During an experiment, a student observes the formation of a precipitate. a chemical reaction is likely occurring because <span>A gas forms, and there is a change of color.</span>
Answer:
1. CaO + H₂O ----> Ca(OH)₂
Compound ----- Compound
2. 2 Na + Cl₂ ----> 2 NaCl
Element ----- Element
3. 2 SO₂ + O₂ ----> 2 SO₃
Element ----- Compound
Mercury (ii) oxide is made up of mercury and oxygen. The total mass of mercury (ii) oxide is 14.2 g, after decomposition 13.2 g of mercury were formed, therefore the mass of oxygen 1 g (14.2 g -13.2 g).
Percentage of oxygen = (1/14.2)×100 = 7.04%
Percentage of mercury = (13.2/14.2) × 100 = 92.96%
Therefore, percentage composition of the compound, oxygen is 7.04% and mercury is 92.96%.
Answer:
You need to add 400mL of water
Explanation:
500mL = 5 M HCI That means that if you divide both sides by 5
100mL = 1 M HCI If you need ot get rid of 4 M HCI then you add 400 mL of water because that is what it is equal to
Dimitri Mendeleev was inspired primarily by the work of Antoine Lavoisier and his work on writing the first extensive list of known elements. Lavoisier also collaborated in the construction of the metric system and worked to develop a better nomenclature for chemical compounds which parts are still used today.