<span>Answer: 8.15s
</span><span />
<span>Explanation:
</span><span />
<span>1) A first order reaction is that whose rate is proportional to the concenration of the reactant:
</span><span />
<span>r = k [N]
</span><span />
<span>r = - d[N]/dt =
</span><span />
<span>=> -d[N]/dt = k [N]
</span><span />
<span>2) When you integrate you get:
</span><span />
<span>N - No = - kt
</span>
<span></span><span /><span>
3) Half life => N = No / 2, t = t'
</span><span />
<span>=> No - No/ 2 = kt' => No /2 = kt' => t' = (No/2) / k
</span><span />
<span>3) Plug in the data given: No = 0.884M, and k = 5.42x10⁻²M/s
</span>
<span /><span /><span>
t' = (0.884M/2) / (5.42x10⁻²M/s) = 8.15s</span>
A .
1 mol of sodium na atoms -22.99
22.99 x 8 =183.92
Closest answer
Statement 1 is false because heat is the movement of molecules.
Statement 2 is true because matter is composed of elementary particles which are VERY small.
Statement 3 is false because the kinetic energy of a particle determines its heat and it is impossible for a particle to be completely motionless.
Statement 4 is false because neutrons do not have a charge and make up a large portion of all matter.
Number of moles:
1 mole ---------- 6.02x10²³ molecules
? moles --------- 9.45x10²⁴ molecules
1 x ( 9.45x10²⁴) / 6.02x10²³ =
9.45x10²⁴ / 6.02x10²³ => 15.69 moles of CH3OH
Therefore:
Molar mass CH3OH = 32.04 g/mol
1 mole ------------ 32.04 g
15.69 moles ----- mass methanol
Mass methanol = 15.69 x 32.04 / 1 => 502.7076 g
Answer:
The war of the currents, sometimes called battle of the currents, was a series of events surrounding the introduction of competing electric power transmission systems in the late 1880s and early 1890s.
Explanation: