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A 25 g substance has a temperature increase of 17’c when it absorbs 340 J of heat. What is it’s specific heat?

Irina-Kira [14]

Answer:

25 x 17 x 340

Explanation:

5 0

3 years ago

A compound has the following percentages by mass: barium, 58.8%; sulfur, 13.74%; oxygen, 27.43%. Determine the empirical formula

lys-0071 [83]

Answer:

BaSO₄

Explanation:

Let's assume we have 100 g of the compound. If that's the case we would have:

58.8 g of Ba

13.74 g of S

27.43 g of O

Now we convert the masses of each element into moles, using their respective molar masses:

58.8 g Ba ÷ 137.327 g/mol = 0.428 mol Ba

13.74 g S ÷ 32 g/mol = 0.429 mol S

27.43 g O ÷ 16 g/mol = 1.71 mol O

We divide those moles by the lowest number among them:

0.428 mol Ba / 0.428 = 1

0.429 mol S / 0.428 ≈ 1

1.71 mol O / 0.428 = 4

We can express those results as Ba₁S₁O₄, meaning the empirical formula is thus BaSO₄.

5 0

3 years ago

[ 6.5 ] In the space below, briefly explain why the average times for the two CO2 molecules you calculated should have been simi

julsineya [31]

Answer:

This question is incomplete

Explanation:

This question is incomplete but there are two parts to this question that can generally be answered without the missing parts.

(1) If a CO₂ molecule starts out surrounded by other CO₂ molecules, does this influence how quickly it will reach the other side of the leaf?

What controls how quickly a CO₂ molecule/molecules enter into the leaf to the other parts of a leaf is the stomata on the leaf. Stomata are tiny openings on a plant leaf that allows for gaseous exchange (the release of oxygen and the absorption of CO₂) in the leaf.

(2) Collisions influence how molecules move, but do molecules only collide with other molecules of the same substance? NO

One of the kinetic theory of gases states that gases collide with one another and against the walls of the container. It should however be noted that, gas molecules of a particular substance can collide with gas molecules of other substances, so far they are within the same container.

5 0

3 years ago

In a vacuum, with no air resistance, how do 2 objects of different weights compare when falling?

viva [34]

Answer

hope it helps

Explanation:

In real life, heavier objects sometimes fall faster than light objects, but not because of gravity. Gravity makes all objects increase their speed at the same rate, regardless of how big they are. But if you drop 2 things outside, the air molecules may slow down one thing more than another.

7 0

4 years ago

How many dm3 of hydrogen are released when 3 g of potassium is reacted with hydroiodic acid?

nlexa [21]

Answer:

V = 0.0859dm³

Explanation:

Hydroiodic acid, HI, reacts with potassium, K, to produce potassium iodide, KI, and hydrogen, as follows:

2HI + 2K → 2KI + H₂(g)

To solve this question we have to find the moles of hydrogen produced knowing that 2 moles of K produce 1 mole of H₂. With the moles of hydrogen we can find the volume of hydrogen assuming there are STP conditions:

Moles K -Molar mass: 39.0983g/mol-

3g * (1mol / 39.0983g) = 0.0767 moles of K

Moles H₂:

0.0767 moles of K * (1mol H₂ / 2mol K) = 0.03836 moles H₂

Using: PV = nRT; V = nRT / P

Where V is volume in dm³,

n are moles of gas: 0.03836 moles,

R is gas constant = 0.082atm*dm³/molK

T is absolute temperature = 273.15K at STP

and P is pressure = 1atm

The volume of the gas is:

V = 0.03836mol*0.082atm*dm³/molK*273.15K / 1atm

8 0

3 years ago