Which symbol can be used to indicate the pressure at which a chemical reaction is carried out? 25 degrees celsius over a right arrow. delta over a right arrow. 2 a t m over a right arrow. upper p t over a right arrow.

2 atm

Explanation:

Chemical reactions are carried out at a certain rate. Sometimes that rate is quite slow, so we want to speed things up, which is usually used by increasing temperature, increasing pressure or adding a catalyst (a substance that increases the rate without changing itself).

If this is the case, then, when writing a chemical equation, we state these special conditions over a right arrow.

Now let's look at the answers:

- 25°C is a value and unit of temperature

- ∆ is a symbol that denotes change

- 2 atm is a value and unit of pressure (atmosphere is old unit for pressure)

- Pt is a chemical symbol for platinum, an element often used as a catalyst.

So, the correct answer is C) 2 atm

false

because it does not have the potential to be entirely used up

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the have energy higher than those in the orbital while lower than those of the orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the orbital is therefore filled right after orbitals and before orbitals.  

potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.