The zinc case in the dry cell battery serves as the

A 4 kg rock is rolling 10 m/s find its kinetic energy

larisa [96]

The answer is 200 J

The kinetic energy (KE) is:
KE = 1/2 m * v²
m - mass of the object
v - velocity of the object

We have:
m = 4 kg
v = 10 m/s

KE = 1/2 * 4 kg * 10² m/s
KE = 200 J

5 0

2 years ago

The density of concentrated ammonia, which is 28.0% w/w nh3, is 0.899 g/ml. what volume of this reagent should be diluted to 1.0

vlada-n [284]

Answer: 2.4 ml

Solution :

Molar mass of $NH_3$ = 17 g/mole

Given,: 28% w/w of $NH_3$ solution means 28 g of ammonia in 100 g of solution.

Mass of solution = 100 g

Now we have to calculate the volume of solution.

$Volume=\frac{Mass}{Density}=\frac{100g}{0.899g/ml}=111.2ml$

Molarity : It is defined as the number of moles of solute present in one liter of solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n = moles of solute $NH_3=\frac{\text {given mass}}{\text {molar mass}}=\frac{28}{17}=1.65moles$

$V_s$ = volume of solution in liter = 0.11 L

Now put all the given values in the formula of molarity, we get

$Molarity=\frac{1.65moles}{0.11L}=15mole/L$

Using molarity equation:

$M_1V_1=M_2V_2$

$15\times V_1=0.036\times 1.0\times 10^{3}$

$V_1=2.4ml$

6 0

3 years ago

How will the following changes affect the mole fraction of chlorine gas, χcl2, in the equilibrium mixture.?

sammy [17]

If the reaction is represented by:
PCl₃ + Cl₂ <-> PCl₅ (exothermic)

the mole fraction of chlorine in the equilibrium mixture will change according to the following:
Decrease the volume: decrease
Increase the temperature: increase
Increase the volume: increase
Decrease the temperature: decrease

4 0

2 years ago

Find the volume of 20g of H₂ at STP<br><br>

ANEK [815]

Answer:224

Explanation:

We should answer it with Stoichiometry

We say: 20 g H2× (1 mol/ 2g)× ( 22.4 lit/ 1 mol) = 224

Means: we have 20 grams and every 2g H2, equals to 1 mol of it and every 1 mol of H2, equals to 22.4 lit( because of STP)

hope you got this:)

6 0

2 years ago

Consider dissolving sugar in water and magnesium sulfate in water. is any new substance being produced? what happens after sodiu

Olenka [21]

Answer:

Here's what I get

Explanation:

1. Sugar

(a) Dissolving in water

The white solid dissolves in water to give a colourless solution. There is no evidence that a new substance is being produced.

(b) Addition of sodium hydroxide

Adding the colourless solution of sodium hydroxide to the colourless sugar solution gives a colourless solution. There is no evidence that a new substance is being produced.

2. Magnesium sulfate

(a) Dissolving in water

The colourless crystals dissolve in water to give a colourless solution. There is no evidence that a new substance is being produced.

(b) Addition of sodium hydroxide

Adding the colourless solution of sodium hydroxide to the colourless solution of magnesium sulfate gives a white precipitate (see image). This is evidence that a new substance is being produced.

8 0

2 years ago