Question

A partially dried clay mineral contains 8%
water. The original sample contained 12%
water and 45% silica. The % of silica in the
partially dried sample is nearly?

Answer 1

Given:

• The % water in original sample = 12%
• The % silica in original sample = 45%
• The % water in partially-dried sample = 8%

To find:

The % silica in the partially-dried sample.

Solution:

• Let the mass of the original sample be x .
• Mass of silica in the original sample (w1) = 0.45x
• Mass of water in the original sample (w2) = 0.12x
• Mass of water in the partially dried sample (w3) = 0.8x
• Mass lost = w2-w3 = 0.04x
• Mass of the partially dried sample (w) = x-0.04x = 0.96x
• % silica in the partially-dried sample = w1*100/w = 46.875%

Answer:

The % silica in the partially-dried sample = 46.875%