How do we separate cork and lead

A stock bottle of an acid reads: 56% by mass and 1.25 specific gravity. If the molar mass of the acid is 70g, find the mole per

TiliK225 [7]

Answer:

10 mol / dm³

Explanation:

Cubic decimeter is the same unit as liter; so, mole per cubic decimeter is mole per liter, and that is the unit of concentration of molarity. Thus, what is asked is the molarity of the solution. This is how you find it.

1. Take a basis: 1 dm³ = 1 liter = 1,000 ml

2. Calculate the mass of 1 liter (1,000 ml) of solution:

density = mass / volume ⇒ mass = density × volume

Here, the density is given through the specific gravity

Scpecific gravity = density of acid / density of water

Take density of water as 1.00 g/ml.

density of solution = 1.25 g/ml

mass solution = 1.25 g/ml × 1,000 ml = 1,250 g

3. Calculate the mass of solute (pure acid)

% m/m = (mass of solute / mass of solution) × 100

56 = mass of solute / 1,250 g × 100

mass of solute = 56 × 1,250g / 100 = 700 g

4. Calculate the number of moles of solute:

moles = mass in grams / molar mass = 700 g / 70 g/mol = 10 mol

5. Calculate molarity (mol / dm³)

M = number of moles of solute / liter of solution = 10 mol / 1 liter = 10 mol/liter.

5 0

2 years ago

A student needed to make a 3 g/L NaCl solution. The student weighed 3 g of NaCl in a beaker and measured 1 L of water in a 1L vo

hoa [83]

Answer:

The answer is in the explanation.

Explanation:

A solution is defined as the homogeneous mixture of a solute (In this case, NaCl) and the solvent (water).

To prepare 1L of the solution, the student can weigh the 3g of NaCl in the volumetric flask but need to add slowly water to dissolve the NaCl (That is very soluble in water). When all NaCl is dissolved the student must transfer the solution to the 1L volumetric flask. Then, you must add more water to the beaker until "Clean" all the solute of the beaker to transfer it completely to the volumetric flask.

8 0

2 years ago

Which refers to the chemical name for NO2?

Anna35 [415]

Answer:

C

Explanation:

6 0

2 years ago

Read 2 more answers

What is the difference between atomic mass, relative atomic mass and average atomic mass

vesna_86 [32]

$\bold{\huge{\underline{\purple{ Answer }}}}$

Difference between Atomic mass, relative atomic mass and average atomic mass :-

<h3>Atomic Mass :-</h3>

Atomic mass is the mass of neutrons and protons present in the nucleus of an atom .
It is always calculated for a single element and having direct value
For isotopes also, the atomic mass is calculated separately . Example :- Carbon 12 , carbon 13 and carbon 14 have different atomic mass. 
The SI unit of Atomic mass is " u" and "amu"

<h3>Relative Atomic mass :-</h3>

Relative atomic mass is mean mass of the atoms of an element which is compared to the 1/12th mass of carbon - 12 .
Carbon - 12 is taken as a relative when we calculate the relative atomic mass of any element
For calculating relative atomic mass, we need to know the masses, percentage and abundance of all types of elements
Relative atomic mass is a dimension less quantity

<h3>Average Atomic Mass :-</h3>

Average atomic mass is the average mass of an atoms of a particular element by considering it's isotopes
While we calculate average atomic mass is a standardized number. Whereas, Average atomic mass sometimes varies geologically .
It also includes percentage, abundance and masses of given element .
In average atomic mass, We do not compare mean value with the 1/12 mass of carbon - 12
The unit of Average atomic mass is "Amu" or " u " .

5 0

2 years ago

Which explains how burning a magnesium ribbon highlights a toolmark?

Setler [38]

<h2>Answer:</h2>

The magnesium ribbon, D. It forms a material to cast the tool mark.

<h2>Explanation:</h2>

When a magnesium ribbon is burnt in the presence of oxygen it gives out strong light and heat is produced. Apart from it, it leads to the production of substance called as magnesium oxide which is formed as the product due to the reaction of magnesium with the oxygen present in the air.

Tool marks are the mark which is created by tools while using them. In order to identify or locate them castes made up of magnesium oxide is utilized. When this is pasted on the suspected area, the tool mark of the suspected tool gets pasted on it.

6 0

3 years ago

How do we separate cork and lead​

How do we separate cork and lead