4.1 h = 14760 s
<span>t 1/2 = ln 2 / k </span>
<span>k = rate reaction = 4.97 x 10^-5 </span>
<span>ln 0.045 / 0.36 = - 4.97 x 10^-5 t </span>
<span>2.08 = 4.97 x 10^-5 t </span>
<span>t = 41839.9 s = 11 h 37 min 19 s</span>
C. Ta
Tantalum is an element with an atomic number of 63 and its electronic configuration is:
[Xe] 4f¹⁴ 5d³ 6s²
Answer:
Pangaea
Explanation:
About 300 Million Years Ago, Earth Didn't Have Seven Continents But Instead Earth Had One Massive Super continent Called Pangaea.
Answer: 43.3 l
Explanation:
1) Chemical equation:
2 Li(s) + 2 H₂O (l) → 2LiOH(aq) + H₂ (g)
2) Mole ratios:
2 mol Li : 2 mol H₂O : 2 mol LiOH : 1 mol H₂
3) Number of moles of Li that react
n = mass in grams / atomic mass = 24.6g / 6.941 g/mol = 3.54 moles
4) Yield
Proportion:
2 mol Li / 1 mol H₂ = 3.54 mol Li/ x
⇒ x = 3.54 mol Li × 1 mol H / 2 mol Li = 1.77 mol H₂
4) Ideal gas equation
PV = nRT ⇒ V = nRT / P
V = 1.77 mol × 0.0821 [atm×l / (mol×K)] × 301 K / 1.01 atm = 43.3 l
V = 43.3 l ← answer
Answer: Group 14
Explanation:
It's a carbon atom with 4 valance electrons.