Diffusion occurs due to differences in _____. A) size B) concentration C) temperature D) collisions

The modern periodic table is arranged in order of increasing. true or false

qaws [65]

Answer:

Increasing atomic number - True

Explanation:

The modern table is based on Mendeleev’s table, except the modern table arranges the elements by increasing atomic number instead of atomic mass.

The Atomic number is the number of protons in an atom, and this number is unique for each element. For example, Hydrogen has an atomic number of 1, Calcium has an atomic number of 20.

In the modern periodic table the elements are further arranged into:

- rows, called periods, in order of increasing atomic number. Elements in the same periods have the same number of shells.

- vertical columns, called groups, where the elements have similar properties. Elements in the same group has the same number of valency (outermost number of electrons)

4 0

3 years ago

Chemistry: Molarity and Concentrations

kotegsom [21]

I dont know if this correct, but i hope it help

5 0

2 years ago

which statement best describes the equation caco3 2hcl → cacl2 co2 h2o? caco3 is a reactant; it is present before the reaction o

fomenos

Answer: $CaCO_3$ is a reactant; it is present before the reaction occurs.

Explanation:

In a chemical reaction the chemical formulas written before the arrow are described as reactants as they react together to form products which are written after the arrow.

$CaCO_3 + 2HCl \rightarrow CaCl_2 + CO_2 + H_2O$

Thus $CaCO_3$ and HCl are reactants here whereas $CO_2$ , $CaCl_2$ and $H_2O$ are products.

7 0

3 years ago

Read 2 more answers

A 25.0g sample of brass, which has a specific heat capacity of 0.375·J·g−1°C−1, is dropped into an insulated container containin

Angelina_Jolie [31]

Answer:

The equilibrium temperature of water is 25.6 °C

Explanation:

Step 1: Data given

Mass of the sample of brass = 25.0 grams

The specific heat capacity = 0.375 J/g°C

Mass of water = 250.0 grams

Temperature of water = 25.0 °C

The initial temperature of the brass is 96.7°C

Step 2: Calculate the equilibrium temperature

Heat lost = heat gained

Q(sample) = -Q(water)

Q = m*C* ΔT

m(sample)*c(sample)*ΔT(sample) = - m(water)*c(water)*ΔT(water)

⇒m(sample) = the mass of the sample of brass = 25.0 grams

⇒with c(sample) =The specific heat capacity = 0.375 J/g°C

⇒with ΔT = the change of temperature = T2 - T1 =T2 - 96.7 °C

⇒with m(water) = the mass of the water = 250.0 grams

⇒with c(water) = the specific heat capacity = 4.184 J/g°C

⇒with ΔT(water) = the change of temperature of water = T2 - T1 = T2 - 25.0°C

25.0 * 0.375 * (T2 - 96.7) = - 250.0 * 4.184 J/g°C * (T2 - 25.0°C)

9.375T2 - 906.56 = -1046T2 + 26150

9.375T2 + 1046T2 = 26150 + 906.56

1055.375T2 = 27056.26

T2 = 25.6 °C

The equilibrium temperature of water is 25.6 °C

4 0

3 years ago

A sample of 19 mg of 9-fluorenone is dissolved in 5 mL of diethyl ether. The resulting organic

maks197457 [2]

Answer:

15.70mg would remain

Explanation:

Partition coefficient is used to extract or purify a solute from a solvent selectively to avoid interference from other substances. For the problem, formula is:

Kp = Concentration 9-fluorenone in ether / Concentration of solute in H₂O

After the solute, 9-fluorenone, is extracted with water, the mass that remains in ether is:

(19mg - X)

<em>Where X is the mass that now is in the aqueous phase</em>

Replacing in Kp formula:

9.5 = (19mg - X) / 5mL / (X /10mL)

0.95X = 19mg - X / 5mL

4.75X = 19 - X

5.75X = 19

X = 19 / 5.75

X = 3.30mg

That means 9-fluorenone that remain in the ether layer is:

19mg - 3.30mg =

<h3>15.70mg would remain</h3>

8 0

3 years ago