Answer is "C".
<em><u>Explanation
</u></em>
Single replacement reaction is a type of reaction which one reactant reacts with another and makes a product by replacing one element by another.
Mg (Magnesium) reacts with Al₂O₃ (Aluminium oxide) and produces MgO (Magnesium oxide) and Al (Aluminium) as products. Here Al is replaced by Mg. Reaction is
Mg + Al₂O₃ → MgO + Al
To balance the reaction equation, both left and right hand sides should have same number of atoms in each element.
Here,
<em>Left Hand Side has </em> <em>Right Hand Side has</em>
Mg = 1 atom Mg = 1 atom
Al = 2 atom Al = 1 atom
O = 3 atom O = 1 atom
First step : balance the O atoms in both sides. To do that "3" should be added before MgO.
Second step : After balancing O atoms, there will be 3 Mg atoms in right hand side. Hence to balance Mg atoms again "3" should be added before Mg in left hand side
Third step : as the final step balance the Al atoms by adding "2" before Al in the right hand side.
Then final balanced equation should be
3Mg + Al₂O₃ → 3MgO + 2Al
Answer:
1.21 g of Tris
Explanation:
Our solution if made of a solute named Tris
Molecular weight of Tris is 121 g/mol
[Tris] = 100 mM
This is the concentration of solution:
(100 mmoles of Tris in 1 mL of solution) . 1000
Notice that mM = M . 1000 We convert from mM to M
100 mM . 1 M / 1000 mM = 0.1 M
M = molarity (moles of solute in 1 L of solution, or mmoles of solute in 1 mL of solution). Let's determine the mmoles of Tris
0.1 M = mmoles of Tris / 100 mL
mmoles of Tris = 100 mL . 0.1 M → 10 mmoles
We convert mmoles to moles → 10 mmol . 1mol / 1000mmoles = 0.010 mol
And now we determine the mass of solute, by molecular weight
0.010 mol . 121 g /mol = 1.21 g
Answer:
. A closed system allows only energy transfer but no transfer of mass. Example: a cup of coffee with a lid on it, or a simple water bottle. ... In reality, a perfectly isolated system does not exist, for instance hot water in a thermos flask cannot remain hot forever.
Answer:
He will decide which drink is to be served to whom, by the use of litmus paper.
Explanation:
The litmus paper is the most common indicator to determine the acidity or basicity of a solution. Blue litmus paper changes its color to red when a solution changes from basic to acidic while red litmus paper changes its color to blue when the opposite occurs (acid → basic).
First of all the litmus paper strip, pH indicator, is immersed in a solution and allowed to pass between 10 and 15 seconds while keeping the strip submerged. Afterwards it is removed, and then the strip compares the color. If the color is diffuse, there is a color scale where it is determined which solution has alkaline or acidic pH
