The shape of the illuminated portion of the Moon as seen by an observer, usually on Earth:

What is the physical state of the products in MgCl2(aq)+2Na(s) -> 2NaCl(aq)+Mg(s)

Degger [83]

Answer:

In your example, sodium reacts with magnesium chloride in a single displacement reaction.

3 0

3 years ago

Read 2 more answers

Give the name and formula of the compound formed from the following elements: (a) cesium and bromine; (b) sulfur and barium; (c)

WARRIOR [948]

Answer: (a) cesium and bromine : $CsBr_2$

(b) sulfur and barium: $BaS$

(c) calcium and ﬂuorine : $CaF_2$

Explanation:

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

The nomenclature of ionic compounds is given by:

1. Positive is written first.

2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.

(a) cesium and bromine: Here cesium is having an oxidation state of +1 called as $Cs^{+}$ cation and bromine $Br^{-}$ is an anion with oxidation state of -1. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral $CsBr$ called as cesium bromide.

(b) sulfur and barium : Here barium is having an oxidation state of +2 called as $Ba^{2+}$ cation and sulphur $S^{2-}$ is an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral $BaS$ . called as barium sulfide.

(c) calcium and ﬂuorine: Here calcium is having an oxidation state of +2 called as $Ca^{2+}$ cation and fluorine $F^{-}$ is an anion with oxidation state of -1. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral $CaF_2$ . called as calcium fluoride.

6 0

4 years ago

When of a certain molecular compound X are dissolved in of benzene , the freezing point of the solution is measured to be . Calc

puteri [66]

The question is incomplete. Here is the complete question.

When 2.10 g of a certain molecular compound X are dissolved in 65.0 g of benzene (C₆H₆), the freezing point of the solution is measured to be 3.5°C. Calculate the molar mass of X. If you need any additional information on benzene, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to 2 significant digits.

Answer: MM = 47.30 g/mol.

Explanation: There is a relationship between freezing point depression and molality. With this last one, is possible to calculate molar mass or molar weight of a compound.

Freezing Point Depression occurs when a solute is added to a solvent: the freezing point of the solvent decreases when a non-volatile solute is incremented.

Molality or molal concentration is a quantity of solute dissolved in a certain mass, in kg, of solvent. Its symbol is m and it's defined as

$m=\frac{moles(solute)}{kg(solvent)}$

Freezing point depression and molal are related as the following:

$\Delta T_{f}=K_{f}.m$

where

$\Delta T_{f}$ is freezing point depression of solution

$K_{f}$ is molal freezing point depression constant

m is molality

Now, to determine molar mass, first, find molality of the mixture:

$\Delta T_{f}=K_{f}.m$

$m=\frac{\Delta T_{f}}{K_{f}}$

For benzene, constant is 5.12°C/molal. Then

$m=\frac{3.5}{5.12}$

m = 0.683 molal

Second, knowing the relationship between molal and moles of solute, determine the last one:

$m=\frac{moles(solute)}{kg(solvent)}$

$mol(solute)=m.kg(solvent)$

mol(solute) = 0.683(0.065)

mol(solute) = 0.044 mol

The definition for Molar mass is the mass in grams of 1 mol of substance:

$n(moles)=\frac{m(g)}{MM(g/mol)}$

$MM=\frac{m}{n}$

In the mixture, there are 0.044 moles of X, so its molecular mass is

$MM=\frac{2.1}{0.044}$

MM = 47.30 g/mol

The molecular compound X has molecular mass of 47.30 g/mol.

7 0

3 years ago

Two difference between molecular formula and molecular weight please help :((

Volgvan

Answer: Formula weight is the sum of weights of all the atoms in an empirical formula of a molecule. Molecular weight is the collection of weights of all the atoms in a molecular formula.

Explanation:

8 0

3 years ago

An archer shot a 0.06 kg arrow at a target. The arrow accelerated at 5,000 m/s/s to reach a speed of 50.0 m/s as it left the bow

nordsb [41]

<h3>Answer;</h3>

C. 300 N

<h3>Explanation;</h3>

From Newton second's Law of motion, the resultant force is directly proportional to the rate of change in momentum.

Therefore;

F = ma ; where F is the resultant force, m is the mass and a is the acceleration.

Therefore;

F = 0.06 kg × 5,000 m/s/s

= 300 N

8 0

3 years ago