Using the ideal gas equation:
PV = nRT
Substituting n with mass / Mr
PV = mRT/Mr
Density = m/V
So rearranging:
Density = PMr/RT
P = 1 atm
R = 0.082 L atm / K mol
T = 273 K
Density = (1 x 80.6) / (0.082 x 273)
Density = 3.6 g / L
Given:3.40g sample of the steel used to produce 250.0 mLSolution containing Cr2O72−
Assuming all the Cr is contained in the BaCrO4 at the end.
(0.145 g BaCrO4) / (253.3216 g BaCrO4/mol) x (250.0 mL / 10.0 mL) x (1 mol Cr / 1 mol BaCrO4) x (51.99616 g Cr/mol / (3.40 g) = 0.219 = 21.9% Cr
Answer: A Confucian
Explanation:
In the year 2005, the Guinness Book of World Records recognized the Confucius genealogical line as the longest family tree in history. They have a record of 86 generations over 2,500 years. Confucius (551 to 479 BCE) is believed to have about 3 million descendants all over the world.
So the interest Melissa has in her family tree and also wanting to know how her family has changed over its many generations probably suggests that Melissa more closely resembles a Confucian.
Every science experiment should follow the basic principles of proper investigation so that the results presented at the end are seen as credible.
Observation and Hypothesis. ...
Prediction and Modeling. ...
Testing and Error Estimation. ...
Result Gathering and Presentation. ...
Conclusions. ...
Law Formation.
Answer: There are 78.26 mL of a 0.0023M strontium hydroxide solution are needed to completely react 15.0 mL of 0.012M hydrochloric acid.
Explanation:
Given: 
= 0.0023 M, 
= ?
= 15.0 mL, 
= 0.012 M
Formula used to calculate volume of strontium hydroxide solution is as follows.
Substitute the values into above formula as follows.
Thus, we can conclude that there are 78.26 mL of a 0.0023M strontium hydroxide solution are needed to completely react 15.0 mL of 0.012M hydrochloric acid.
