# Weight percentage and grams per liter

I was reading some documents that said 25 wt. %, 500 mlL-1 as well as 20 gL-1

I think 25 wt. %, 500 mlL-1 is referencing 25% weight of 500 ml of water so that would be 125 ml of water

20 g*L-1 would be 20 g per liter but since the reference is 500 ml then I should reduce this formula to 10 g to fit the 500 ml.

Is that correct?

$$\text{NiSO}_4\cdot6\text{H}_2\text{O}\quad\left(20\ \text{g}\cdot\text{L}^{-1}\right)$$ $$\text{NH}_3\quad\left(25\ wt.\%,\ 500\ \text{ml}\cdot\text{L}^{-1}\right)$$

• This question is hard to follow with the spacing and sentence structure. Would you please edit it to make it more clear? Also, can you include the section that you read as an attachment or direct quotation? Nov 27 '19 at 13:36
• I am unsure how to properly write the markdown, therefore i uploaded an image with the proper formatting. Nov 27 '19 at 14:06
• The question lacks important information for us to answer it clearly. What is compound that is being considered? Pure water? Something dissolved in water? How are these three different composition values actually quoted? Why are they in parentheses? Nov 27 '19 at 14:33
• I've converted your image to markdown, send me a direct message if you want me to run through how it's constructed - you didn't pick the simplest thing to start with! Nov 27 '19 at 17:29
• And I've added the <sup>...</sup>markdown for superscript. Add a space between numbers and unit symbols as per SI standard and as per "4 carrots" rather than "4carrots". Nov 27 '19 at 22:04

## 1 Answer

No. The nickel sulfate hydrate needs to be dissolved in water so that you have 20g per litre. The ammonia-water solution needs to be present as 500ml per litre. The 25% is just relating to the ammonia concentration to use (33% being the maximum at RTP).
The ratio to use should be in your article as it looks like you're making an ammoniacal nickel precipitate. However your question was using this example to obtain a generic understanding. If you see a % sign, if it's telling you how to make a concentration, it will usually have w/w, v/v or w/v after it(weight-weight, volume-volume and weight-volume respectively). For this sort of question, I would post in Chemistry.