Does anyone know where i can find a practice cumulative chem test online?

1 answer:

Montano1993 [528]3 years ago

6 0

Exam board websites often have past papers from several previous years, if you know what exam board you are going to be using, try that, if not there may be content on the edexcel and AQA websites

You might be interested in

A water treatment plant applies chlorine for disinfection so that 10 mg/L chlorine is achieved immediately after mixing. The vol

Vlada [557]

Answer: The mass of chlorine needed by the plant per day is $9.4625\times 10^8mg$

Explanation:

We are given:

Volume o water treated per day = 25,000,000 gallons

Converting this volume from gallons to liters, we use the conversion factor:

1 gallon = 3.785 L

So, $\frac{3.785L}{1\text{ gallon}}\times 25,000,000\text{ gallons}=9.4625\times 10^7L$

Amount of chlorine applied for disinfection = 10 mg/L

Applying unitary method:

For 1 L of water, the amount of chlorine applied is 10 mg

So, for $9.4625\times 10^7L$ of water, the amount of chlorine applied will be $\frac{10mg}{1L\times 9.4625\times 10^7L}=9.4625\times 10^8mg$

Hence, the mass of chlorine needed by the plant per day is $9.4625\times 10^8mg$

6 0

3 years ago

What is the oxidation number of chlorine

sergiy2304 [10]

The oxidation number of chlorine in the Cl- ion is -1.

3 0

3 years ago

A sample of ammonia gas at 75°c and 445 mm hg has a volume of 16.0 l. what volume will it occupy if the pressure rises to 1225 m

ioda

In this kind of exercises, you should use the "ideal gas" rules: PV = nRT
P should be in Pascal:
445mmHg = 59328Pa
1225mmHg = 163319Pa

V should be in cubic meter:
16L = 0.016 m3

R = $\frac{PV}{nT}$ = constant
$\frac{P1 V1}{n T}$ = $\frac{P2 V2}{n T}$
==> P1 * V1 = P2 * V2
V2 = $\frac{P1 V1}{P2}$ = $\frac{445 0.016}{1225}$
V2 = 0.00581 m3 = 5.81 L

7 0

4 years ago

Calculate the boiling point of a solution of 500.0 g of ethylene glycol (c2h6o2) dissolved in 500.0 g of water. kf = 1.86Â°c/m a

Bingel [31]

Answer:The boiling point of the solution is 108° C.

Explanation:

Boiling point of pure water=T= $100^oC$