Question
A 60-liter solution contains 30% alcohol. How much pure
alcohol must be added to make the solution 50% alcohol?Solution
Currently, the solution contains 30% of 60 liters = 18 liters of alcohol. Let x liters of pure alcohol be added. After adding x liters, total volume = 60 + x liters, Alcohol = 18 + x liters. We want: (18 + x) / (60 + x) = 0.5. Solving gives: 18 + x = 0.5(60 + x), 18 + x = 30 + 0.5x, 0.5x = 12, x = 24 liters. Answer: a) 24 liters
Specific heat of aluminum when 26000 J of energy is supplied to 4 kg block and it's temperature rises from 25°C to 35°C is
What would happen to the weight of a body in a lift moving upward with uniform speed?
Which of the following element is found in maximum percentage in the human body?
The SI unit of mechanical power is:Â
Natural radioactivity was discovered byÂ
Which gas is used in the process of photosynthesis?
If two bodies of different masses, initially at rest, are acted upon by the same force for the same time, then the both bodies acquire the same -
The escape velocity from a planet is 11.2 km/s. What is the minimum kinetic energy per kg needed to escape?
1. 6.3 x 107 J/ Kg
<...What is the minimum distance one has to stand at from a wall to hear an echo?
Which gas turns lime water milky?
