• Hydrogen is only slightly ( or poorly , or sparingly ) soluble .
• Helium has only a slight solubility .
• Hydrogen is only slightly ( or poorly , or sparingly ) soluble .
• Helium has only a slight solubility .
Циммерман М., Веденеева К.. Русско-Английский научно-технический словарь переводчика. Russian-English scientific dictionary for translators. 2012