Answer:
6.79 atm
Explanation:
Applying Dalton's law of partial pressure:
, where 
= total partial pressure of all the component gases in the mixture, 
= partial pressure of helium gas, and 
= partial pressure of oxygen gas.
From the illustration, = 7.00 atm and = 0.21 atm. Hence, the partial pressure due to helium is calculated such that:
= 
= 7.00 - 0.21
= 6.79 atm
<em>Therefore, the partial pressure due to helium in order to maintain the pressure due to oxygen at 0.21 atm would be </em><em>6.79 atm.</em>
Given the criteria, there are six because there are three Carbon dioxide molecules and di means two; so two times three us six. But if u look at the whole reaction *pictured below* u will see that in the entire reaction there are 10 Oxygen reacting through the whole thing.
*the triangle is the Greek letter delta and it symbolizes heat in a reaction.
Answer:
The electron took two jumps to return to its ground state.
Explanation:
If the electron is in nth state then it first goes to (n-1)th to 2nd state and emits one photon of this energy gap. Then, it goes to ground state and emits another photon of different energy. It can emit 
types of different photons. Fourth option is incorrect because in that case it emits one photon and absorbs one photon to go back to that state and also both photons are of same energy.
Bromothymol blue is acid base indicator which has pH intervals 6 - 7.6 and its two colors are yellow in acid and blue in basic.
The pH of CaO is about 11.5 to 12.5 this will make the indicator has blue color at the beginning.
By bubbling CO₂ to CaO this leads to formation of CaCO₃ which also basic (pH about 9.5 - 10) so the color of indicator remains blue
No color change of the indicator will observed (remains blue)
The answer to the questions. All 15 of them.
