chemistry

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how do i do this \?

a 4.0mg/dl standard solution is needed. To prepare 100ml of the working standard. How much stock standard of a 1mg/ml (100mg/dl) solution is needed.

i don't understand this conceptually /

thanks

  • chemistry -

    I don't get it either. Perhaps if you wrote all of the question and used proper punctuation the question might make sense.

  • chemistry -

    problem 2

    copies straight from my notes

    a 4.0mg/dL standard solution is needed. To prepare 100mL of the working standard, how much stock standard of a 1mg/mL solution is neeeded ?

    i emailed her:I didn\t know what is a stock standard , working etc.

    Stock standard is a standard prepared from manufacturer which is the most concentrated solution. It is then diluted to make a working standard in the lab. That working standard will be used as a standard to calibrate instrument or used for the experiment. It will become clearer after next week's lab. We'll be making serial dilution from a stock standard next week.

    So in other words, the question is asking how many ml of stock standard with a concentration of 1 mg/ml needed to make 100 ml of 4.0 mg/dl concentration working standard.

    thanks

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