Reaction type __HCl + __Mg -> __MgCl2 + _

Answer number 1 please

kkurt [141]

Answer:

C. is the answer simple.

6 0

3 years ago

A scientist measures the speed of sound in a monatomic gas to be 449 m/s at 20∘C. What is the molar mass of this gas?

Ivan

Answer:

The molar mass of the gas is 36.25 g/mol.

Explanation:

To solve this problem, we can use the mathematical relation:

ν = $\sqrt{3RT/M}$

Where, ν is the speed of light in a gas (ν = 449 m/s),

R is the universal gas constant (R = 8.314 J/mol.K),

T is the temperature of the gas in Kelvin (T = 20 °C + 273 = 293 K),

M is the molar mass of the gas in (Kg/mol).

ν = $\sqrt{3RT/M}$

(449 m/s) = √ (3(8.314 J/mol.K) (293 K) / M,

by squaring the two sides:

(449 m/s)² = (3 (8.314 J/mol.K) (293 K)) / M,

∴ M = (3 (8.314 J/mol.K) (293 K) / (449 m/s)² = 7308.006 / 201601 = 0.03625 Kg/mol.

∴ The molar mass of the gas is 36.25 g/mol.

7 0

3 years ago

Electrons are found in energy levels around the nucleus of an atom. Energy levels can also be called ""shells."" The energy leve

melamori03 [73]

Answer:

The first electronic shell or energy level, having n= 1, called the K shell, is the closest to the nucleus.

Explanation:

In an atom, the sub atomic particles called electrons, revolve around the nucleus of the given atom at different energy levels, called shells.

The energy levels or the electronic shells are denoted by the principal quantum number (n) and has the following values n = 1, 2, 3, 4, 5, 6, 7; from the innermost shell to the outermost.

The electron shells are also labelled by the alphabets, K, L, M, N, O, P, and Q, from the innermost shell to the outermost.

Thus the first electronic shell having n= 1, called K shell, is the lowest energy level and is present closest to the nucleus.

Whereas, the last electronic shell having n =7, called Q shell, is the highest energy level and is farthest from the nucleus.

5 0

3 years ago

Explain how sodium and calcium react with water. explain with equations

34kurt

Reaction of sodium with water

Sodium metal reacts rapidly with water to form a colourless solution of sodium hydroxide (NaOH) and hydrogen gas (H2). The resulting solution is basic because of the dissolved hydroxide. The reaction is exothermic. During the reaction, the sodium metal may well become so hot that it catches fire and burns with a characteristic orange colour. The reaction is slower than that of potassium (immediately below sodium in the periodic table), but faster than that of lithium (immediately above sodium in the periodic table).

2Na(s) + 2H2O → 2NaOH(aq) + H2(g)

4 0

3 years ago

Mr. Chem S. Tree added water to 250. ML of a 2.50 M NaOH solution, until the final volume was 500. ML. What is the new molarity

tresset_1 [31]

Answer:

molarity of diluted solution = 1.25 M

Explanation:

Using,

C1V1 (Stock solution) = C2V2 (dilute solution)

given that

C1 = 2.50M

V1 = 250ML

C2 = ?

V2 = 500ML

2.50 M x 250 mL = C2 x 500 mL

C2 = (2.50 M x 250 mL) / 500 mL

C2 = 1.25 M

Hence, molarity of diluted solution = 1.25 M

4 0

3 years ago

Reaction type __HCl + __Mg -> __MgCl2 + __H2

Reaction type HCl + Mg -> MgCl2 + H2