PLEASE HELP!!!

Which list of elements is arranged in order of increasing electronegativity?

muminat

K, ca, sc is the right answer. Take a look at table S of your chemistry reference table.

6 0

3 years ago

If substances B and C are both in the gas phase and are at the same energy level, which of the two substances will need to have

ss7ja [257]

Answer:

Substances can change phase—often because of a temperature change. At low temperatures, most substances are solid; as the temperature increases, they become liquid; at higher temperatures still, they become gaseous.

The process of a solid becoming a liquid is called melting. (an older term that you may see sometimes is fusion). The opposite process, a liquid becoming a solid, is called solidification. For any pure substance, the temperature at which melting occurs—known as the melting point—is a characteristic of that substance. It requires energy for a solid to melt into a liquid. Every pure substance has a certain amount of energy it needs to change from a solid to a liquid. This amount is called the enthalpy of fusion (or heat of fusion) of the substance, represented as ΔHfus. Some ΔHfus values are listed in Table 10.2 “Enthalpies of Fusion for Various Substances”; it is assumed that these values are for the melting point of the substance. Note that the unit of ΔHfus is kilojoules per mole, so we need to know the quantity of material to know how much energy is involved. The ΔHfus is always tabulated as a positive number. However, it can be used for both the melting and the solidification processes as long as you keep in mind that melting is always endothermic (so ΔH will be positive), while solidification is always exothermic (so ΔH will be negative).

6 0

3 years ago

The _______ force is a noncontact force that is created by the movement of an electrical charge. A. centrifugal B. electromagnet

Nataliya [291]

the answer for your question is B. Electromagnetic. because electric charge is the physical property that causes it to experience force when it is placed in a electromagnetic field the electric charge is carried by subatomic particles which causes the movement of the magnetic force

6 0

3 years ago

Read 2 more answers

ryan is a chemistry student that enjoys hot tea. he wants to determine how much ice is needed to cool 250.0 ml of tea to an opti

mestny [16]

Ryan calculates that he requires 4 ice cubes for 250mL of hot tea to reach the optimal drinking temperature by using the specific heat capacity of tea.

A substance's potential to hold heat is indicated by its specific heat capacity. This substance size reflects the amount of heat required to raise a certain volume of a material's temperature by one Kelvin. Specific heat capacity is a distinguishing feature of every substance and is useful for material identification.

Given:

Final temperature of system is 57.8℃

dT1 = 79.1 - 57.8 = 21.3℃

dT2 = 0 - (-8.33) = 8.33℃

dT3 = 57.8 - 0 = 57.8℃

Mass of tea, m1 = 250.0mL = 250.0g = 0.250kg

Specific heat capacity of tea, C1 = 4186 J/kg℃ = Specific heat capacity of water

Specific heat capacity of ice, Ci = 2090 J/kg℃

Mass of each ice cubes, m of i = 18.8g

Latent heat of fusion of ice, Lf = 334 kJ/kg

To find:

No. of ice cubes required = ?

Calculations:

Suppose equilibrium temperature is T, then

Heat released by Tea = Heat gained by Ice

Q1 = Q2

m1x C1x dT1 = mi x Ci x dT2 + mi x Lf + mi x Cw x dT3

0.250x 4186 x 21.3 = mi x (2090 x 8.33 + 3.34 x $10^4$ + 4186 x 57.8)

mi = 0.250 x 4186 x 21.3 / (2090 x 8.33 + 3.34 x $10^4$ + 4186 x 57.8)

mi = 0.0761kg = 76.1g

Mass of ice required = 76.1g

Number of ice cube required will be:

n = Total mass of ice/mass of each ice cube

n = 76.1/18.8

n = 4.04 ice cubes = 4.0 ice cubes

Result:

Ryan requires 4 ice cubes to bring 250mL of hot tea to the optimal drinking temperature.

Learn more about Specific heat capacity here:

brainly.com/question/24265493

#SPJ4

7 0

1 year ago

How do you do problem #15?

SVETLANKA909090 [29]

You would convert the cg to g. 1.66 cg is 0.0166 g. then you add. 0.398 + 0.0166 = 0.4146. the answer is 0.4146 grams.

7 0

3 years ago