Examine the chemical equation Al + O2 Al2O3

Emission Spectrum Questions for Quiz Print - Quizizz

-Dominant- [34]

Isotopes of the same element

₃₅⁷⁷X and ₃₅⁸¹X

<h3>Further explanation</h3>

Given

Isotopes of element

Required

Isotopes of the same element

Solution

The elements in nature have several types of isotopes

Isotopes are elements that have the same Atomic Number (Proton) and different mass numbers

Element symbols that meet the 2 conditions above are :

₃₅⁷⁷X and ₃₅⁸¹X

3 0

1 year ago

Rank the following solutions in order of increasing acidity (least acidic to most acidic): I: [H3O+] = 1x10−5 II: [OH−] = 1x10−1

kozerog [31]

Answer: option C) II < III < I

i.e [OH−] < [H3O+] < I

Explanation:

First, obtain the pH value of I and II, then compare both with III.

For I

Recall that pH = -log (H+)

So pH3O = -log (H3O+)

= - log (1x10−5)

= 4

For II

pOH = - log(OH-)

= - log(1x10−10)

= 9

For III

pH = 6

Since, pH range from 1 to 14, with values below 7 to be acidic, 7 to be neutral, above 7 to be alkaline: then, 9 < 6 < 4

Thus, the following solutions from least acidic to most acidic is II < III < I

6 0

2 years ago

Suppose you were required to make a solution by diluting 20.0 mL of an aqueous solution to a final volume of 750 mL.

torisob [31]

The first thing you do before performing anything in the laboratory is to read the procedure and prepare the materials needed. Next, if you already have the solution where you are supposed to take your 20 mL sample, then have it near you. Then, prepare a volumetric flask (750 mL) and a 20-mL pipette. Wash the pipette 3 times with the sample solution. If your diluent is water, wash the flask 3 times with water. Now, get 20 mL of sample from your parent solution, then add it to the flask (previously washed with water). Finally, add water until the mark in the flask and make sure that the water added is up to the mark based on the lower meniscus reading to be accurate in the amount inside the flask. <span />

7 0

2 years ago

Iron is biologically important in the transport of oxygen by red blood cells from the lungs to the various organs of the body. I

Aneli [31]

Answer : The number of iron atoms present in each red blood cell are, $1.077\times 10^9$

Explanation :

First we have to calculate the moles of iron.

$\text{Moles of iron}=\frac{\text{Mass of iron}}{\text{Molar mass of iron}}=\frac{2.90g}{55.85g/mole}=0.0519moles$

Now we have to calculate the number of iron atoms.

As, 1 mole of iron contains $6.022\times 10^{23}$ number of iron atoms

So, 0.0519 mole of iron contains $0.0519\times 6.022\times 10^{23}=3.125\times 10^{22}$ number of iron atoms

Now we have to calculate the number of iron atoms are present in each red blood cell.

Number of iron atoms are present in each red blood cell = $\frac{\text{Number of iron atoms}}{\text{Total number of red blood cells}}$

Number of iron atoms are present in each red blood cell = $\frac{3.125\times 10^{22}}{2.90\times 10^{13}}$

Number of iron atoms are present in each red blood cell = $1.077\times 10^9$

Therefore, the number of iron atoms present in each red blood cell are, $1.077\times 10^9$

6 0

2 years ago

PLEASE HELP WILL GIVE BRAINLIEST

aleksklad [387]

Answer:

Explanation:

Gravity pulls the balls down the ramp, and the force of gravity is bigger on larger-mass objects. The extra force on the bigger ball means that it has more energy when it gets to the bottom of the ramp and consequently travels more before stopping.

6 0

2 years ago