Answer: The number 4 indicates 4 electrons.
Explanation: We are given an electronic configuration, which is:

Here,
- The letters denote the sub-shells of an element.
- The numbers written before the letters which are 1, 2 and 2 represents the Principle Quantum Number and these represents the energy level of the sub-shells.
- The number which are written in the superscripts which are 2, 2 and 4 denotes the electrons which are present in the sub-shell.
Hence, 4 indicates 4 electrons present in 2p sub-shell.
- According to Pascal’s principle, for a certain fluid in a totally enclosed system, a change in pressure at a given point in the fluid is transferred to all points in the fluid, as well as to the enclosing walls.
- This is illustrated by the fact that the pressure inside an enclosed system is the same according to the relation [ pressure = force/area ]. Therefore, the change in pressure resulting from squeezing a ketchup bottle will be transferred equally to all parts of that bottle as well as its internal content.
- That’s how hydraulic machines, such as garbage trucks and hydraulic lifts function..
Answer:
im pretty sure its 2...
Explanation:
if its wrong im sorry
if its right brainliest pls?
Answer:
m H2(g) = 2.241 g H2(g)
Explanation:
- 2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3 H2(g)
limit reagent:
∴ Mw Al = 26.982 g/mol
∴ Mw H2SO4 = 98.0785 g/mol
⇒ n Al = (20 g Al)×(mol/26.982 g) = 0.7412 mol Al
⇒ n H2SO4 = ( 115 g H2SO4 )×(mol/98.0785 g) = 1.173 mol H2SO4
⇒ n H2 = (0.7412 mol Al)×(3 mol H2/ 2 mol Al) = 1.112 mol H2
∴ Mw H2 = 2.016 g/mol
⇒ g H2 = (1.112 mol H2)×(2.016 g/mol) = 2.241 g H2