Berapa gram CuSO4.5 H2O harus ditimbang untuk membuat 100 mL larutan yang mengandung Cu2+ 1000 ppm?

<p>Jawaban &nbsp;<strong>392,91 mg</strong></p><p>&nbsp;</p><p><strong>Pembahasan&nbsp;</strong></p><p>1 ppm = 1 mg/kg</p><p>Jika dianggap densitas larutan adalah 1 g/mL maka 1 ppm = 1 mg/L</p><p>&nbsp;</p><p>1000 ppm = 1000 mg/L</p><p>maka&nbsp;</p><p>dlm 100 mL larutan = 100/1000 x 1000 mg/L</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 100 mg Cu²⁺</p><p>&nbsp;</p><p>Mr CuSO4. 5H2O = 63,5 + 32 + 4×16 + 5×18</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; = 249,5</p><p>&nbsp;</p><p>Massa CuSO4. 5H2O yg harus ditimbang:</p><p>100 : (63,5/249,5) = 392,91 mg</p><p>&nbsp;</p>