What is the name of the ionic compound rbcl?

Select the equations below that represent physical changes.

Ierofanga [76]

Physical changes- any change in the physical properties of the substance is a physical change. Generally physical properties include color, state, size , shape, odour, appearance . In any phyical change, no new substance is formed.

Chemical changes- any change in the chemical properties of the substance is a chemical change. Chemical properties changes only when something new is formed during a reaction.

∴ Part A- 2 H2O(l) → 2 H2(g) + O2(g)

In this, H2 and O2 is produced during the reaction which is different from H20. Thus, it is a chemical change.

Part B- H2O(l) → H2O(s)

In this, only the state of water changes from liquid to solid and no new product is formed. Thus, it is a physical change.

Part C-CO2(s) → CO2(g)

In this also, only the state of CO2 changes from solid to gas and no new product is formed. Thus, it is a physical change.

Part D-H2(g) → 2 H(g)

In this reaction, H2 molecule is dissociated into 2 hydrogen atom leading to formation of new products. Thus, it is a chemical change.

Finally, equations that represent physical changes are - B and C

B. H2O(l) → H2O(s)

C. CO2(s) → CO2(g)

6 0

3 years ago

A gas effuses 1.55 times faster than propane (C3H8)at the

stepladder [879]

Answer: The mass of the gas is 18.3 g/mol.

Explanation:

To calculate the rate of diffusion of gas, we use Graham's Law.

This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:

$\text{Rate of diffusion}\propto \frac{1}{\sqrt{\text{Molar mass of the gas}}}$

$\frac{Rate_{X}}{Rate_{C_3H_8}}=1.55$

$\frac{Rate_{X}}{Rate_{C_3H_8}}=\sqrt{\frac{M_{C_3H_8}}{M_{X}}}$

$1.55=\sqrt{\frac{44}{M_{X}}$

Squaring both sides and solving for $M_{X}$

$M_{X}=18.3g/mol$

Hence, the molar mas of unknown gas is 18.3 g/mol.

5 0

3 years ago

Read 2 more answers

A 70.0-g piece of copper metal at 86.0 ∘c is placed in 50.0 g of water at 16.0 ∘c. The metal and water come to the same temperat

valentina_108 [34]

Copper is current voltage above 40 or 200 . copper useful for motor and some medicine

4 0

3 years ago

4. Substances that existed before mixing-still exist-after substances-are-mixed----

pantera1 [17]

False; Because when 2 substances are mixed another substance is created.

5 0

3 years ago

Two atoms with different numbers of protons are what?

Gnom [1K]

Answer:

c) two different elements

Explanation:

A periodic table can be defined as the standard arrangement of chemical elements by atomic number, electronic configuration and chemical properties in a tabular form.

Generally, a proper representation of the mass number and atomic number of chemical elements is key and very important in chemistry.

Furthermore, as a rule, it should be noted that the mass number (nucleon number) is always larger than the atomic number(number of proton).

In the periodic table, all chemical elements are identified based on number of protons because it represents the atomic number.

This ultimately implies that, numbers of protons (atomic numbers) is used to differentiate an atom of one chemical element from the atom of another chemical element.

Hence, two atoms with different numbers of protons are two different elements.

For example, Hydrogen has one proton while Oxygen has 8 protons.

6 0

3 years ago