Answer:
It will take 5492 seconds to electroplate 0.5 mm of gold on an object .
Explanation:
Mass of gold = m
Volume of gold = v
Surface area on which gold is plated = 
Thickness of the gold plating = h = 0.5 mm = 0.05 cm
1 mm = 0.1 cm
Density of the gold = 
Moles of gold = 
According to reaction, 1 mole of gold required 3 moles of electrons,then 0.152 moles of gold will require :
of electrons
Number of electrons = N =
Charge on single electron = 
Total charge required = Q
Amount of current passes = I = 8 Ampere
Duration of time = T
It will take 5492 seconds to electroplate 0.5 mm of gold on an object .
Answer:
When solutions of sodium carbonate and hydrochloric acid are mixed, the equation for the hypothetical double displacement reaction is: Na2CO3 + 2 HCl → 2 NaCl + H2CO3 Bubbles of a colorless gas are evolved when these solutions are mixed.
Answer:
4.78 %.
Explanation:
<em>mass percent is the ratio of the mass of the solute to the mass of the solution multiplied by 100.</em>
<em></em>
<em>mass % = (mass of solute/mass of solution) x 100.</em>
<em></em>
mass of MgSO₄ = 50.0 g,
mass of water = d.V = (0.997 g/mL)(1000.0 mL) = 997.0 g.
mass of the solution = mass of water + mass of MgSO₄ = 997.0 g + 50.0 g = 1047.0 g.
<em>∴ mass % = (mass of solute/mass of solution) x 100</em> = (50.0 g/1047.0 g) x 100 = <em>4.776 % ≅ 4.78 %.</em>
H2O=18.01g/mole. 210g divided by 18.01g/mole=11.653mole. 1 mole has 6.22x10^23 molecules. So there is 11.653x(6.22x10^23) molecules. Just multiply 11.653 by 6.22. Then put it as answerx10^23 molecules
