1M NaCl solution is 58.5 g/1000 ml , where molecular wt of NaCl being 58.5 grams , so 29.2 g of NaCl in 1000 ml of water will be equal to : 29.2g /58.5g = 0.499145299 M , so 29.2 g NaCl dissolved in 100 ml would correspond to , 0.499145299 M X 1000 ml/100 ml = 4.99145 M or about 4.99 M
