PLEASE HELP The arrows in the chart below represent phase transitions.

How many grams hydrogen in 4.5 mol H2SO4

swat32

H2SO4 ---> 2H^+ + SO4^2-

Hence n H+ = 9 mols

Mass of H = nM = (9*1) = 9g

Alternately

mass of H2SO4= nM= 4.5*98= 441

Mass of H= mass h2so4 * molar mass of H/molar mass of h2so4
Mass of H= 441 * 2/98 = 9g

4 0

3 years ago

a calorimeter contained 75.0 g of water at 16.95 C. A 93.3-g sample of iron at 65.58 C was placed in it, giving a final temperat

Nostrana [21]

Answer:- $\frac{382.69J}{0C}$ .

Solution:- Mass of Iron added to water is 93.3 g. Initial temperature of iron metal is 65.58 degree C and final temperature of the system is 19.68 degree C.

temperature change, $\Delta T$ for iron metal = 65.58 - 19.68 = 45.9 degree C

specific heat for the metal is given as 0.444 J per g per degree C.

let's calculate the heat lost by iron metal using the equation:

$q=mc\Delta T$

where, q is the heat energy, m is mass, c is specific heat and delta T is change in temperature. let's plug in the values and calculate q for iron metal:

$q=93.3g(45.9^0C)(\frac{0.444J}{g.^0C})$

q = 1901.42 J

Using same equation we will calculate the heat gained by water.

mass of water is 75.0 g.

$\Delta T$ for water = 19.68 - 16.95 = 2.73 degree C

specific heat for water is 4.184 J pr g per degree C. Let's plug in the values:

$q=75.0g(\frac{4.184J}{g.^0C})(2.73^0C)$

q = 856.674 J

Total heat lost by iron metal is the sum of heat gained by water and calorimeter.

So, heat gained by calorimeter = heat lost by iron metal - geat gained by water

heat gained by calorimeter = 1901.42 J - 856.674 J = 1044.746 J

Change in temperature for calrimeter is same as for water that is 2.73 degree C

For calorimeter, $q=C.\Delta T$

$C=\frac{q}{\Delta T}$

$C=\frac{1044.746J}{2.73^0C}$

$C=\frac{382.69J}{0C}$

So, the heat capacity of calorimeter is $\frac{382.69J}{0C}$ .

4 0

3 years ago

How much work is done in moving a load 15 meters using a force of 15 Newton’s

Svetradugi [14.3K]

Answer: 225 joules.

Explanation:

If this a one dimension problem, this is the motion is in the same direction of the force, the equation for work is:
Work = distance × force
⇒ Work = 15 m × 15 N = 225 joules.
This is a special case of the general equation

Work = |F| |displacement| cosine (angle between the force and displacement)

When force and displacement are in the same direction, the angle is 0, so cos(0) = 1. This is the two vectors are parellel and the work is just the product of the two magnitudes (force and distance)

3 0

3 years ago

spaghetti takes about 9 minutes to cook at sea level, but about 14 minutes in the mountains. why do you think this happens???

Ivahew [28]

Water boils when the vapor pressure of the water equals the atmospheric pressure that's pressing down on it. Water boils at a lower temperature (more easily) at higher elevations (like on mountains), because:

- Atmospheric pressure is lower at higher elevation

- Easier for vapor pressure to equal this lower atmospheric pressure

Since the water boils at a lower temperature, it takes longer for the pasta to cook.

3 0

3 years ago

Read 2 more answers

A jar is filled with water, and the lid is closed tightly. The jar is kept at constant temperature. What happens at the surface

nata0808 [166]

If there is a close container with some water, the following procedures take place.
Initially, the system contains only liquid, and air above it. As evaporation starts (the rate of evaporation is constant for the specific temperature of the water), the molecules from the surface of the liquid escape into vapour state, in the confined space above. Therefore, the level of liquid falls.
Then starts the process of condensation. This is the conversion of vapour into liquid. Initially, escaped molecules (from liquid state) move randomly in all directions and collide with one another. As more and more molecules enter the confined space, some slow-moving molecules are pushed back. They collide with the surface of the liquid to reconvert into liquid.
In the initial stages, the rate of evaporation (constant) is more than the rate of condensation because only small number of molecules are present in the gaseous state. The rate of condensation thereafter gradually increases as the number of molecules in the gaseous phase increases. Finally, a stage is reached when the rate of the two opposing processes is the same.
The state where the rate of evaporation becomes equal to the rate of condensation is called a state of dynamic equilibrium. In such a state, although the amount of liquid level in the container does not change, evaporation has not stopped and the system is not at rest. In fact, the number of molecules, which escape from the liquid to the gaseous phase (due to evaporation), becomes equal to the number of vapour molecules that return to the liquid

4 0

3 years ago