Molarity is given as,
Molarity = Moles / Volume of Solution ----- (1)
Also, Moles is given as,
Moles = Mass / M.mass
Substituting value of moles in eq. 1,
Molarity = Mass / M.mass × Volume
Solving for Mass,
Mass = Molarity × M.mass × Volume ---- (2)
Data Given;
Molarity = 2.8 mol.L⁻¹
M.mass = 101.5 g.mol⁻¹
Volume = 1 L (I have assumed it because it is not given)
Putting values in eq. 2,
Mass = 2.8 mol.L⁻¹ × 101.5 g.mol⁻¹ × 1 L
Mass = 284.2 g of CuF₂
The balanced equation :
2NaHCO₃⇒CO₂ + Na₂CO₃+H₂O
<h3>Further explanation</h3>
Given
Reaction
NaHCO(s) --> _CO2+_NaCO(s)+_H2O
Required
The balanced equation
Solution
Maybe the equation should be like this :
NaHCO₃⇒CO₂ + Na₂CO₃+H₂O
Give a coefficient
NaHCO₃⇒aCO₂ + bNa₂CO₃+cH₂O
Make an equation
Na, left=1, right=2b⇒2b=1⇒b=1/2
H, left=1, right=2c⇒2c=1⇒c=1/2
C, left=1, right=a+b⇒a+b=1⇒a+1/2=1⇒a=1/2
The equation becomes :
NaHCO₃⇒1/2CO₂ +1/2Na₂CO₃+1/2H₂O x2
2NaHCO₃⇒CO₂ + Na₂CO₃+H₂O
<u>Answer:</u>
Pyrite leaves behind a green-black streak when it is rubbed against an unglazed porcelain plate as a part of the streak test process.
<u>Explanation:</u>
Different minerals produce different coloured streaks when rubbed against a white ceramic or porcelain streak plate. This streak test is done to identify the mineral and distinguish the same from other minerals that look similar in colour and texture.
It must be ensured that the test is done on clean and fresh specimens of the mineral and that there must be no contaminants. Pyrite specimens are usually brass-yellow colour but it leaves a green-black streak when the streak test is done.
Answer:
Gravitation Potential Energy
Explanation: