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Sonja [21]
3 years ago
9

What trends were seen in medeleevs periodic table

Chemistry
1 answer:
Paraphin [41]3 years ago
8 0

Answer:

groups are based on how many electrons to become stable

Explanation:

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Assume that a point mutation changes the codon AUU to AUC. Why is this a neutral mutation
lukranit [14]
I used the genetic code table. mRNA codon ===> amino acid

1st base       2nd base           3rd base
A                       U                             U               ===> Isoleucine
A                       U                             C               ===> Isoleucine

The point mutation of codon AUU to AUC is a neutral mutation because it neither benefits nor deter the ability of the organism to survive and reproduce.

As you can see, Both codons result to the Isoleucine amino acid.

Another codon that will still result to the Isoleucin amino acid is AUA.

3 0
3 years ago
What material is the source for commercial production of each of the following elements:(a) aluminum;
AleksandrR [38]

The material which is used as source for commercial production aluminum is bauxite.

The aluminum can be extracted from bauxite ore by the process of Bayer process.

In the Bayer process, bauxite ore is heated in the pressure vessel along with a caustic soda solution (sodium hydroxide) at a temperature between 150 to 200 °C. At this temperatures, the aluminium is dissolved in the solution as sodium aluminate in the extraction process. After separation of the residue by filtering, when the liquid is cooled gibbsite is precipitated and then it is seeded with fine-grained aluminum hydroxide crystals from previous extractions. The precipitation take 7-19 days without the addition of seed crystals.

This extraction process converts the aluminium oxide to soluble sodium aluminate, NaAlO2, which afterward converted into aluminum hydroxide and then into aluminum oxide.

Thus, we concluded that the material which is used as source for commercial production aluminum is bauxite ore.

learn more about ore:

brainly.com/question/10306443

#SPJ4

3 0
1 year ago
What is the mass of 4.99×1021 platinum atoms?
charle [14.2K]

Answer:

\boxed {\boxed {\sf 1.62 \ g \ Pt}}

Explanation:

We are asked to find the mass of a number of platinum (Pt) atoms.

<h3>1. Convert Atoms to Moles </h3>

First, we convert atoms to moles using Avogadro's Number or 6.022 × 10²³. This is the number of particles (atoms, molecules, formula units, etc.) in 1 mole of a substance. In this case, the particles are platinum atoms.

We will convert using dimensional analysis so we set up a ratio using the information we know (6.022 × 10²³ platinum atoms in 1 mole of platinum).

\frac {6.022 \times 10^{23} \ atoms \ Pt}{ 1 \ mol \ Pt}

We are converting 4.99 ×10²¹ atoms of Pt to moles of Pt, so we multiply by this value.

4.99 \times 10^{21} \ atoms \ Pt *\frac {6.022 \times 10^{23} \ atoms \ Pt}{ 1 \ mol \ Pt}

Flip the ratio so the units of atoms of platinum cancel.

4.99 \times 10^{21} \ atoms \ Pt *\frac { 1 \ mol \ Pt}{6.022 \times 10^{23} \ atoms \ Pt}

4.99 \times 10^{21} *\frac { 1 \ mol \ Pt}{6.022 \times 10^{23}}

\frac { 4.99 \times 10^{21}}{6.022 \times 10^{23}} \ mol \ Pt

Divide.

0.008286283627 \ mol \ Pt

<h3>2. Convert Moles to Grams </h3>

Next, we convert moles to grams using the molar mass. This is the mass of 1 mole of a substance. This is found on the Periodic Table because it is equivalent to the atomic mass, but the units are grams per mole instead of atomic mass units. Look up platinum's molar mass.

  • Pt: 195.08 g/mol

Set up another ratio using this new information (195.08 grams of Pt in 1 mole of Pt).

\frac {195.08 \ g \ Pt}{ 1 \ mol \ Pt}

Multiply by the number of moles we just calculated.

0.008286283627 \ mol \ Pt*\frac {195.08 \ g \ Pt}{ 1 \ mol \ Pt}

The units of moles of platinum cancel.

0.008286283627*\frac {195.08 \ g \ Pt}{ 1 }

0.008286283627* {195.08 \ g \ Pt}

1.61648821\ g \ Pt

<h3>3. Round</h3>

The original measurement of atoms ( 4.99 ×10²¹ ) has 3 significant figures, so our answer must have the same. For the number we found, that is the hundredth place. The 6 in the thousandth place tells us to round the 1 up to a 2.

1.62 \ g \ Pt

There are approximately <u>1.62 grams of platinum</u> in 4.99 ×10²¹ atoms of platinum.

8 0
3 years ago
Which is a set of valid quantum numbers?
Mariana [72]

The last set which is n=4 l=3 m=3 is a valid set

7 0
3 years ago
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What is kinetic energy
lina2011 [118]

It's the form of energy in a moving object or a particle. It is present in any object that has a mass and a speed.

Kinetic energy = 1/2 mv²

7 0
2 years ago
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