The periodic law describes trends seeing across which of the following?

What is thr total of all the forces on an object .

Katen [24]

Is the combination of all forces acting on an object

6 0

4 years ago

2.00 L of a gas is collected at 25.0°C and 745.0 mmHg. What is the volume at 760.0 mmHg

Leviafan [203]

1.7960L

Explanation:

the mass of the gas is constant in both instances

pv/T=constant(according to pv=nRT)

745mmHg*2L/298K=760mmHg*v/273K

v=1.7960L

5 0

3 years ago

The human body excretes nitrogen in the form of urea, NH₂CONH₂. The key step in its biochemical formation is the reaction of wat

Misha Larkins [42]

Mass perventage of nitrogen in urea, arginine, ornithine is 46.67%, 32.2%,21% respectively.

What is Mass perventage ?

Mass percentage is one way of representing the concentration of an element in a compound or a component in a mixture. Mass percentage is calculated as the mass of a component divided by the total mass of the mixture, multiplied by 100.

Molecular mass of urea (NH2CONH2) is= 2× (Atomic mass of N ) + 4 × (Atomic mass of H) + (Atomic mass of C) (Atomic mass of O) = 60

Mass percentage of N = $Total mass of N atoms in the compoundMass of compound×100=2860×100=46.67%$

chemical formula for arginine is C6H14N4O2

molar mass of C6H14N4O2=174g/mol

moles of N atoms in C6H14N4O2=4

mass of N atoms=14*4=56g

mass percent of N in C6H14N4O2=(56/174)*100=32.2%

the chemical formula for ornithine is C5H12N2O2

molar mass of C5H12N2O2=132g/mol

moles of N atoms in C5H12N2O2=2

mass of N atoms in C5H12N2O2=2*14=28

mass percent of N in C5H12N2O2=(28/132)*100=21%

To learn more about urea click on the link below:

brainly.com/question/17812875

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7 0

1 year ago

The atomic number of polassium and

never [62]

Explanation:

Atomic radius decreases from left to right in a period.

Therefore Calcium would have a smaller atomic size.

6 0

3 years ago

What is meant by the limiting reactant why is it necessary to identify the limiting reactant when you want to know what?

WARRIOR [948]

You have the reactants who react to make your products.

Reactants --------> Products

The limiting reactant is the reactant that will RUN OUT FIRST and that will establish the maximum amount of product that will be produced.

To make an example, let's look at this equation and at the following question:

2Al + 6HCl → 2AlCl3 + 3H2

When 6.0 mol Al react with 13 mol HCl, what is the limiting reactant, and how many moles of H2 can be formed?

We know that 2Al + 6HCL are the reactants, right?

These 2 reactants will react to create an amount of a certain product in this case they're asking us for the amount of H2 that will be produced. Therefore, we need to find the REACTANT it can be either AL OR HCL.

But, how do we know which one is the limiting reactant?

To know which one is the limiting reactant we need to know HOW MUCH H2 can Al produce, and also how much H2 can HCL produce. Why?

It's simple, because if you find the one that produces the less amount of H2, you know immediately that's the maximum amount of that product that will be produced.

Let's say you have a sandwich that needs to be made with 2 slices of bread, 3 meats and 1 cheese.

But you have got 4 slices of bread, 9 slices of meat, and 5 slices of cheese.

Well, you could make 2 sandwiches with 4 slices of bread, 3 sandwiches with those 9 slices of meat and 5 sandwiches with the 5 slices of cheese.

But, in reality, you can only make 2 sandwiches because you don't have any more bread to produce more sandwiches. You get it? That is the point of limiting reactants, to find what is the actual amount that can be produced.

Coming back to our equation, we can find the number of moles of H2 produced by each one of the reactants, Al and HCl. I'll find the number of moles quickly to show you what the concept of limiting reactant is.

6.0mol Al x 3 mol H2/2 mol Al = 9 mol H2

13 mol HCL x 3 mol H2/6 mol HCL = 6.5 mol H2

As you can see, 6.5 mol of H2 is the maximum that can be produced by the HCL and is less than the Al, so that maximum amount that you will get in the product H2 is no more than 6.5.

4 0

4 years ago