Answer:
9 (1-2x²)
Explanation:
The given expression is:
30 - 9x²*2 - 21 - 4 + 4
The first step is to compute the multiplication. This will give:
30 - 18x² - 21 - 4 + 4
Then, we will add like terms as follows:
(30-21-4+4) - 18x²
= 9 - 18x²
Finally, we can take the 9 as a common factor from both terms, this will give:
9 (1-2x²)
Hope this helps :)
Answer: when concentrations of acid and base are same, pH = pKa
PH = 12.38 pOH = 1.62
Explanation: pKa= -log(Ka)= 12.38. PH + pOH = 14.00
Answer:
Ionic
Explanation: Ionic compounds tend to be hard and brittle while covalent compounds tend to be softer and more flexible.
Hope this helped!
Answer:
Option C:- that is equal to mass of an proton.
Explanation:
Protons and neutrons have approximately the same mass, about 1.67 × 10-24 grams, which scientists define as one atomic mass unit (amu) or one Dalton. While electron has mass of 9.31 ×10⁻¹⁹.
Negative because it'll have to gain an electron
