<span>When a chemist mixes oxygen gas and hydrogen gas to form
water, which is composed of one oxygen and two hydrogen atoms per molecule. The hydrogen and oxygen atoms bounds together by making a bond called covalent bond.<span> In a covalent bond, two atoms are bound
together because they each want to "share" each other's electrons.</span></span>
There are several ways of expressing concentration of solution. Few of them are listed below
1) mass percentage
2) volume percentage
3) Molarity
4) Normality
5) Molality
In most of the drugs, concentration is expressed either in terms of mass percentage or volume percentage. For, solid in liquid type systems, mass percentage is convenient way of expressing concentration, while for liquid in liquid type solutions, expressing concentration in terms of volume percentage is preferred. Present system is an example of liquid in liquid type solution
Here, concentration of H2O2 is given antiseptic = 3.0 % v/v
It implies that, 3ml H2O2 is present in 100 ml of solution
Thus, 400 ml of solution would contain 4 X 3 = 12 ml H2O2
Answer:
mass of methanol = 519.3 g
Explanation:
Given data:
molecules of CH3OH = 9.77 × 10∧ 24
mass in gram = ?
Solution:
First of all we will calculate the number of moles:
(9.77 × 10∧ 24) × 1 mol / 6.02 × 10∧23 = 16.229 moles
Now we will calculate the mass in gram:
Formula:
number of moles = mass/ molar mass
16.229 mole = mass / 32 g/mol
mass = 16.229 mol × 32 g/ mol
mass = 519.3 g
Simple method:
molar mass of CH3OH is 32 g so according to Avogadro number,
32 g of CH3OH = 6.02 × 10∧23 molecules
9.77*10^24 molecules will be equal to
(32 g of CH3OH / 6.02 × 10∧23 molecules) × 9.77*10^24 molecules
= 5.136 × 10∧-23 g/molecules × 9.77*10^24 molecules
= 519.3 g
8.908 G/cm^3 is the density of a nickel
Answer (4)
Endothermic processes: are those in which occurs the absorption of heat.
the change of enthalpy (ΔH) is greater <span>than zero.
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hope this helps!