Answer:
The solution is 50 %wt
Explanation:
50% wt is a sort of concentration and means, that 50 g of solute (in this case, the potassium bromide) dissolved in 100 g of water.
It is the same to say, that there are 50g of KBr for every 100g of H₂O
Given :
Human blood should have around 1.04 kg/L platelets.
A blood sample of 4.01 milliliters is collected from a patient to be analyzed for a platelet count.
To Find :
The expected mass in grams of platelets in the blood sample.
Solution :
1 L of human blood contains 1.04 kg of platelets.
So, amount of platelets is 1 ml blood is :
Mass of platelets in 4.01 ml blood is :
Hence, this is the required solution.
We are told that KOH is being used to completely neutral H₂SO₄ according to the following reaction:
KOH + H₂SO₄ → H₂O + KHSO₄
If KOH can completely neutralize H₂SO₄, then there must be an equal amount of moles of each as they are in a 1:1 ratio:
0.025 L x 0.150 mol/L = .00375 mol KOH
0.00375 mol KOH x 1 mole H₂SO₄/1 mole KOH = 0.00375 mol H₂SO₄
We are told we have 15 mL of H₂SO₄ initially, so now we can find the original concentration:
0.00375 mol / 0.015 L = 0.25 mol/L
The concentration of H₂SO₄ being neutralized is 0.25 M.
<h2>The required "options are (II), (III), and (IV)".</h2>
Explanation:
Postulates of Dalton's atomic theory which are scientifically accepted are:
- Atoms are indestructible.
- Compounds are combinations of different atoms.
- A chemical reaction changes the way atoms are grouped together.
Postulates of Dalton's atomic theory which are not accepted scientifically are:
- All atoms of the same elements are identical.
The theory states that the atoms of the same element are identical in every aspect but it is now scientifically proved that the same element should differ in their mass which is known as isotopes.
A pure substance refers to an element or a compound that has no component of another compound or element. Pure substances are made of only one type of atom or molecule. Hydrogen gas and pure iron are examples of pure substances. Hydrogen consists of hydrogen atoms only while iron consists of only iron atoms. Mixing two pure substances results in a mixture. To separate the two, scientists use a method known as filtration. Mixtures can either be homogeneous or heterogeneous. The measure used to determine how pure a substance may be called purity. Besides hydrogen and iron, other pure substances include gold, diamonds, sugar, and baking soda.
