Combustible: Charcoal, straw, cardboard, paper, candle, wood.
Non-combustible: Chalk, stone, iron rod, copper coin, glass.
Answer:
7.43 × 10²⁴ m⁻³
Explanation:
Data provided in the question:
Conductivity of a semiconductor specimen, σ = 2.8 × 10⁴ (Ω-m)⁻¹
Electron concentration, n = 2.9 × 10²² m⁻³
Electron mobility,
= 0.14 m²/V-s
Hole mobility,
= 0.023 m²/V-s
Now,
σ = 
or
σ = 
here,
q is the charge on electron = 1.6 × 10⁻¹⁹ C
p is the hole density
thus,
2.8 × 10⁴ = 1.6 × 10⁻¹⁹( 2.9 × 10²² × 0.14 + p × 0.023 )
or
1.75 × 10²³ = 0.406 × 10²² + 0.023p
or
17.094 × 10²² = 0.023p
or
p = 743.217 × 10²²
or
p = 7.43 × 10²⁴ m⁻³
On the bottom
1. sharing electrons
2. the middle two dots between the F:F
No disadvantage, it’s important have a lid on a crucible to hand extreme temperatures. The lid may also be used to contain chemicals being heated whilst in a lab.
The grams of aluminium oxide are formed when 350 kj heat are released is calculated as follows
1mole = 850Kj
what about 350kj
=1mole x350/850 = 0.412 moles
mass of Al = moles of Al x molar mass of Al
= 0.412mol x 27 g/mol = 11.124 grams