How long will it take a 50w heater to melt 100g of ice at 0°c?

Explanation:

50 W = 50 J /s

Heat required to melt an object is given by the equation

Q = mL , Q is heat required , m is mass to be melted and L is latent heat of fusion

Given mass to be melted m = .1 kg

L = latent heat of fusion of ice = 334000 J / kg

Q = .1 x 334000

= 33400 J

power of heater = 50 J /s

or it gives heat 50 J /s

time required = 33400 / 50

= 668 s

= 11.33 minutes .

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz