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3 years ago

8

The equation for the chemical reaction shown is not balanced. What number should replace the question mark to balance this equat

ion?
2Ag2O → ?Ag + O2

A.
2

B.
3

C.
1

D.
4

1 answer:

Anton [14]3 years ago

3 0

It will be D.4 because you have two lots of 2Ag atoms so its 4 in total

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how many ml of a 22.5% (v/v) ethanol solution would you need to measure out in order to have 12.5 ml of ethanol ?

Aleks [24]

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4 years ago

What is the half-life of a pharmaceutical if the initial dose is 500 mg and only 31 mg remains after 6 hours?

Sergeu [11.5K]

Answer:

$\large \boxed{\text{b. 1.5 h}}$

Explanation:

1. Calculate the rate constant

The integrated rate law for first order decay is

$\ln \left (\dfrac{A_{0}}{A_{t}}\right ) = kt$

where

A₀ and A_t are the amounts at t = 0 and t

k is the rate constant

$\begin{array}{rcl}\ln \left (\dfrac{500}{31}\right) & = & k \times 6\\\\\ln 16.1 & = & 6k\\2.78& =& 6k\\k & = & \dfrac{2.78}{6}\\\\& = & 0.463 \text{ h}^{-1}\\\end{array}$

2. Calculate the half-life

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3 years ago

What is the mass of 1.7 × 1023 atoms of zinc

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3 years ago

A 1.00 g sample of n-hexane (C6H14) undergoes complete combustion with excess O2 in a bomb calorimeter. The temperature of the 1

Nadya [2.5K]

Answer:

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Explanation:

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<em>-negative because the energy is produced-</em>

I hope it helps!

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4 years ago

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