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3 years ago

Elements - made up of Ex:

1 answer:

7 0

All elements are made up of atoms. ➢ Atoms are made up of protons, neutrons, and electrons. Two different kinds of atoms can combine to form a compound. A molecule is a combination of atoms that cannot be broken apart while still retaining the same properties as the larger substance that it is a part of.

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Which formula equation represents the burning of sulfur to produce sulfur dioxide?

Dmitriy789 [7]

Answer:

option A = S(s) + O₂(g) → SO₂ (s)

Explanation:

Chemical equation:

S(s) + O₂(g) → SO₂ (s)

when sulfur burned in the presence of oxygen it produce sulfur dioxide. The sulfur dioxide can further react with oxygen to produce sulfur trioxide and then react with water to form sulfuric acid.

Uses of sulfur dioxde:

It is used as a solvent and reagent in laboratory.

Sulfur dioxide is used to produce sulfuric acid.

It is used as a disinfectant

It is also used as a reducing agent.

It is used to preserve the dry food.

7 0

3 years ago

Examples of electromagnetic wave

dlinn [17]

Answer:

Believe it or not our the light we see "visible light" is an example of electromagnetic wave. other examples include microwaves, radio waves, infrared, ultraviolet, x-rays, and gamma rays.

Explanation:

3 0

3 years ago

Predict whether each of the following molecules is polar or nonpolar? 1. XeF4 3. CCl4 5. CH3Br

denpristay [2]

The answer the following are as follows:

<span> 1. XeF4 - molecules are polar

3. CCl4 - molecules are polar

5. CH3Br - molecules are non-polar

I hope my answer has come to your help. God bless and have a nice day ahead!</span>

5 0

3 years ago

For Na2HPO4:(( (Note that for H3PO4, ka1= 6.9x10-3, ka2 = 6.4x10-8, ka3 = 4.8x10-13 ) a) The active anion is H2PO4- b) The activ

Komok [63]

Answer:

Check the explanation

Explanation:

Answer – Given, $H_3PO_4$ acid and there are three Ka values

$K_{a1}=6.9x10^8, K_{a2} = 6.2X10^8, and K_{a3}=4.8X10^{13}$

The transformation of $H_2PO_4- (aq) to HPO_4^2-(aq)$ is the second dissociation, so we need to use the Ka2 = 6.2x10-8 in the Henderson-Hasselbalch equation.

Mass of KH2PO4 = 22.0 g , mass of Na2HPO4 = 32.0 g , volume = 1.00 L

First we need to calculate moles of each

Moles of KH2PO4 = 22.0 g / 136.08 g.mol-1

= 0.162 moles

Moles of Na2HPO4 = 32.0 g /141.96 g.mol-1

= 0.225 moles

[H2PO4-] = 0.162 moles / 1.00 L = 0.162 M

[HPO42-] = 0.225 moles / 1.00 L = 0.225 M

Now we need to calculate the pKa2

pKa2 = -log Ka

= -log 6.2x10-8

= 7.21

We know Henderson-Hasselbalch equation

pH = pKa + log [conjugate base] / [acid]

pH = 7.21 + log 0.225 / 0.162

= 7.35

The pH of a buffer solution obtained by dissolving 22.0 g of KH2PO4 and 32.0 g of Na2HPO4 in water and then diluting to 1.00 L is 7.35

6 0

2 years ago

Janice bought 40 shares of stock at $31.82 per share. She received dividends of $1.11 per share for 1 year. (Do not use commas,

Alborosie

Answer:

$30.71 per share

Explanation:

The <em>purchase price</em> is what Janice invested for every share.

Since the stock was priced at $31.82 per share and she received a $1.11 dividend per share, her investment was:

$31.82 - $1.11 = $30.71 per share ← answer

This price is the cost for Janice, over which she shall calculate their returns (gains or losses) on the future, when she sells the shares, for instance.

The total investment of Janice was the number of shares multipled by the purchase price:

40 shares × ($31.82 - $1.11)/ share

40 shares × ($30.71) / share = $1,228.40 (total investment)

5 0

2 years ago