8. Which of the following elements reacts like calcium (Ca) but with less atomic
mass?
Potassium (K)
Magnesium (Mg)
Strontium (Sr)
Scandium (Sc)

Answers

Answer 1

Answer:

Magnesium (Mg)

Explanation:

An element with a lower atomic mass than Calcium that has similar chemical property is the element Magnesium (Mg).

This because, elements in the same group or family on the periodic table has similar chemical properties.

Magnesium belongs to the same group as Calcium, other elements are:

     Be  Mg  Ca    Sr  Ba  Ra

The group is made of the alkaline earth metals. They have two valence electrons in their outer shell.


Related Questions

Which describes a chemical property of
copper

Answers

Answer:

Atomic number 29

Atomic mass 63.546 g.mol -1

Electronegativity according to Pauling 1.9

Density 8.9 g.cm-3 at 20°C

Melting point 1083 °C

Copper has a melting point of 1083.4 +/- 0.2°C, boiling point of 2567°C, specific gravity of 8.96 (20°C), with a valence of 1 or 2. Copper is reddish colored and takes a bright metallic luster. It is malleable, ductile, and a good conductor of electricity and heat.

How many electrons are in the outer shell of a Li +1 ion?

Answers

Answer:

3 electrons

Explanation:

That means there are 3 electrons in a lithium atom. Looking at the picture, you can see there are two electrons in shell one and only one in shell two.

Is this true Bc I’m not sure

Answers

Answer:

????? questions there no question

Answer:

what

Explanation:

A container of nitrogen gas contains 0.55 mol at 7.0 atm and 45°C, and it has a volume of 2.0 L. What volume
will 1.20 mol of nitrogen have at 7.0 atm and 45°C?

Answers

Answer:

4.4 L

Explanation:

Given data:

Initial number of mole = 0.55 mol

Initial volume = 2.0 L

Final volume = ?

Final number of moles = 1.20 mol

Temperature and pressure = constant

Solution:

Formula:

V₁/n₁   = V₂/n₂

V₂ = V₁×n₂/n₁  

V₂ = 2.0 L ×1.20 mol/ 0.55 mol

V₂ = 2.4 L.mol / 0.55 mol

V₂ = 4.4 L

The volume of the gas is 31.3 L.

Using the formula;

PV = nRT

P = pressure of the gas

V = volume of the gas

n = Number of moles of the gas

R  gas constant

T = temperature

To obtain the volume;

V = nRT/P

V = 1.20 mol * 0.082 atmLmol-1K-1 * 318 K/7.0 atm

V = 31.3 L

Learn more about volume:

1.How far can you travel if you drive 4 hours and can average 120 Km/hr?
a.30 Km
b.480 Km
c.80 Km

Answers

Answer:

B

Explanation:

D=S×T

=120km/h×4hrs

=480km

Answer:

the answer is b

Explanation:

this is the answer :)

A solution has a pH of 2. Which best describes the solution? A strong acid, a strong base, a neutral solution, a weak base

Answers

Answer:

The best solution is Strong acid

Explanation:

add me on snap Andy142512

A solution that has a pH of 2 is a strong acid solution.

Explanation:

The pH of the solution is defined as the negative logarithm of the hydrogen ions concentration in an aqueous solution.

                            [tex]pH=-\log[H^+][/tex]

If the pH of the solution is less than 7 is said to be an acidic solution.If the pH of the solution is equal to 7 is said to be a neutral solution.If the pH of the solution is greater than 7 is said to be an alkaline solution.

So, from this, we can conclude that solution with a pH of 2 which is less than 7, hence strong acidic solution.

Learn more about the pH of the solution here:

brainly.com/question/4975103?referrer=searchResults

brainly.com/question/172153?referrer=searchResults

GIVING BRAINLY
this equation describes a chemical reaction : aluminum + iron oxide → aluminum oxide + iron
Which of the following statements about the chemical equation is true? * view attachment for answer choices*

Answers

Answer:

C. Iron oxide is a mixture of iron and oxygen

Need Help ASAP
Calculate the pH of:

a) 0.1 M HF Ka = 7.2 x 10-4

b) 1 x 10-3 M HNO3

c) 1 x 10-8 M HCl

Answers

a. pH=2.07

b. pH=3

c. pH=8

Further explanation

pH=-log [H⁺]

a) 0.1 M HF Ka = 7.2 x 10⁻⁴

HF= weak acid

[tex]\tt [H^+]=\sqrt{Ka.M}\\\\(H^+]=\sqrt{7.2.10^{-4}\times 0.1}\\\\(H^+]=8.5\times 10^{-3}\\\\pH=3-log~8.5=2.07[/tex]

b) 1 x 10⁻³ M HNO₃

HNO₃ = strong acid

[tex]\tt pH=-log[1\times 10^{-3}]=3[/tex]

c) 1 x 10⁻⁸ M HCl

[tex]\tt pH=-log[1\times 10^{-8}]=8[/tex]

An ionic compound is formed when:


A) an aluminum ion bonds to a calcium ion

B) a cation bonds to an
anion

C) a neutral compound gains an electron

D) at atom gains an electron

Answers

Answer:

b is the answer .............

Answer:

The asnswer is c

Explanation:

Gope it helps

In order for photosynthesis to take place, energy in the form of ______ is required.

A. Sound

B. Light

C. Electricity

D. Kinetic

Answers

B. Light
Chloroplasts on leaves absorb the sunlight to make energy which is what causes photosynthesis. Hope this helps!

baking soda and vinegar lab demo part 2 mass! 7th grade please help!

Answers

Answer:

just watch the video, what does it start with, write that down for each trial, then what does it end with, then starting mass - ending mass is the change mass

Make the following conversion.

60 dkm = _____ km

6,000
0.060
60,000
0.60

Answers

Answer:

0.6

Explanation:

Melting chocolate (a change of state) is an example of a

Answers

It is an example of a physical change because the chocolate changes from a solid to a liquid however it’s chemical composition is not changed so it’s a physical change.

1. Which of the following is NOT a main tissue type? *

Answers

Answer:

there is nothing follow that

Explanation:

How do mammals protect their young?

Answers

Answer:

Explanation:

Baby pigs, dolphins, bats and elephants all drink milk! Because the babies rely on their mother's milk to live, the mammal mommies have to care for their young. ... Through copying their mothers, baby mammals learn everything they need to survive

Answer:

by be young

Explanation:

wow just use you brain

In an experiment, the gram atomic mass of magnesium was determined to be 14.7. Compared to the accepted value of 24.3, the percent error for this determination was
39.5
1.65
24.7
98.4

Answers

Answer:

The answer is 39.5 %

Explanation:

The percentage error of a certain measurement can be found by using the formula

[tex]P(\%) = \frac{error}{actual \: \: number} \times 100\% \\[/tex]

actual mass = 24.3

error = 24.3 - 14.7 = 9.6

We have

[tex]p(\%) = \frac{9.6}{24.3} \times 100 \\ = 39.506172839...[/tex]

We have the final answer as

39.5 %

Hope this helps you

HELP!!

H2SO4 is _____.

a base
an acid
a neutral

(The 2 is small and so is 4)

Answers

Answer:

Acid

Explanation:

acid

Answer:

An acid

Explanation:

H2OSO4 is Sulfuric Acid

What is a scientific model? How is a scientific model helpful to the brain for relaying a scientific
concept?

Answers

Answer: A scientific model is a physical and mathematical and conceptual representation of a system of ideas, events or processes.

ANd also for your second question i dont know what you mean?

Explanation:

Scientists work to recognize and comprehend patterns in our world by applying their scientific expertise to provide predictions about the patterns.

What is the main purpose of scientific model?

In a range of scientific specialties, from chemistry and physics to biology and the Earth sciences, research models are employed to explain and forecast the behavior of real things or systems. The ability to depict things that are too little or enormous, explain either past or present, and forecast the future are all advantages of employing model beyond nature.

Why are scientific models important?

Models can help you visualize something is difficult to see or understand. Models can help in scientific predictions, process comprehension, and concept communication. Because it frequently includes a variety of hypotheses or facts, an evolutionary theory varies from other general explanations. A science simulation may be used to verify a scientific theory or to demonstrate a scientific model.

To know more about Scientific model visit:

https://brainly.com/question/4737073

#SPJ2

A 2.0 sample of N2 occupy 50.0L at 15 degrees Celsius and 640mmHg. What volume will the gas occupy at 45 degrees Celsius and 160mmHg?

Answers

Answer:

220.8L

Explanation:

Given parameters:

Initial volume  = 50L

Initial temperature = 15°C  = 288K

Initial pressure = 640mmHg

Final temperature  = 45°C  = 318K

Final pressure  = 160mmHg

Unknown:

Final volume  = ?

Solution:

Using the combined law;

        [tex]\frac{p_{1}v_{1} }{T_{1} }[/tex]  = [tex]\frac{p_{2}v_{2} }{T_{2} }[/tex]  

p,v and T are pressure, volume and Temperature

    [tex]\frac{640 x 50}{288}[/tex]  = [tex]\frac{160 x v_{2} }{318}[/tex]

     160 x 288 x v₂ = 640 x 50 x 318

                         v₂ = 220.8L

When heated, calcium carbonate decomposes according to the equation given below:

CaCO3 --> CaO + CO2
If 50.0 g of CaCO3 react but only 20.0 g of CO2 are recovered, what is the percent yield of this reaction?


90.9%
40.0%
66.7%
250%

Answers

Answer:

Percent yield = 90.9%

Explanation:

Given data:

Mass of CaCO₃ = 50.0 g

Mass of CO₂ produced = 20.0 g

Percent yield = ?

Solution:

Chemical equation:

CaCO₃ →  CaO + CO₂

Number of moles of CaCO₃:

Number of moles = mass/molar mass

Number of moles = 50.0 g/ 100.1 g/mol

Number of moles = 0.5 mol

Now we will compare the moles of CO₂ with CaCO₃.

                      CaCO₃          :        CO₂

                          1                :           1

                       0.5               :          0.5

Mass of CO₂: Theoretical yield

Mass = number of moles × molar mass

Mass = 0.5 mol × 44 g/mol

Mass = 22 g

Percent yield:

Percent yield = ( actual yield / theoretical yield ) × 100

Percent yield = (20.0 g/ 22.0 g) × 100

Percent yield = 0.909 × 100

Percent yield = 90.9%

A sample of 5.0 g of hydrogen gas reacts with 5.0 g of oxygen gas.
2H2(g) + O2(g) > 2H2O

Please answer the questions in a b c d and e, or at least in any of the ones you know. Thank you.

Answers

The percent yield of the reaction has been 74.47%.

The balanced chemical equation for the reaction has been:

[tex]\rm 2\;H_2\;+\;O_2\;\rightarrow\;2\;H_2O[/tex]

(a) The theoretical yield can be calculated as:

The theoretical yield of water has been:

1 mole of oxygen produces = 2 moles of water

0.1562 moles of oxygen produces = 0.1562 [tex]\times[/tex] 2

= 0.312 moles of water.

The mass of water has been = moles [tex]\times[/tex] molecular weight

The theoretical yield of water = 0.312 [tex]\times[/tex] 18 grams

The theoretical yield of water = 5.616 grams.

(b) The limiting reactant has been the one whose concentration has been in a lesser quantity for the complete utilization of other reactants.

According to the reaction, for the complete utilization of 2 moles of Hydrogen, 1 mole of oxygen has been used.

The moles of 5 grams Hydrogen:

Moles = [tex]\rm \dfrac{weight}{molecular\;weight}[/tex]

Moles of hydrogen = [tex]\rm \dfrac{5}{1}[/tex]

Moles of hydrogen = 5 mol.

Moles of Oxygen = [tex]\rm \dfrac{5}{32}[/tex]

Moles of oxygen = 0.1562 mol.

For the complete utilization of 5 moles of hydrogen 2.5 moles of oxygen has been required.

Since the oxygen has been present in a lesser quantity, the oxygen has been the limiting reactant.

(c) The consumption of 0.1562 moles of Oxygen has required 0.312 mol of Hydrogen. The hydrogen has been present in a higher quantity than required.

Thus. hydrogen has been the excess reactant.

(d) The remained excess reactant has been:

Remained = Total - consumed

Remained = 5 - 0.312

Remained = 4.68 mol.

The excess reactant has been 4.68 mol extra than required.

(e) The theoretical yield of water has been:

1 mole of oxygen produces = 2 moles of water

0.1562 moles of oxygen produces = 0.1562 [tex]\times[/tex] 2

= 0.312 moles of water.

The mass of water has been = moles [tex]\times[/tex] molecular weight

The theoretical yield of water = 0.312 [tex]\times[/tex] 18 grams

The theoretical yield of water = 5.616 grams.

The actual yield of water has been 4.2 grams.

The percent yield of water = [tex]\rm \dfrac{Actual\;yield}{Theoretical\;yield}\;\times\;100[/tex]

The percent yield of water = [tex]\rm \dfrac{4.2}{5.616}\;\times\;100[/tex]

The percent yield of water = 74.74 %

For more information about the limiting reactant, refer to the link:

https://brainly.com/question/14225536

Answer:

a- 5.616

b- Oxygen

c- hydrogen

d- 4.68 extra

e- 74.47%

I hope this helps! Cheers ^^

Can anyone help me ? Tell me if it is right

Answers

Answer:

yes

Explanation:

When water is solid, do molecules move?

Answers

Answer:

Ice is water in its solid form. Ice keeps its shape, even if it's removed from the container. The molecules in ice are locked into place and cannot move or slide past one another, but they do vibrate a little bit.

Explanation:

As the temperature drops or decreases, the water molecules gradually slow down. Eventually they stop moving and simply vibrate back and forth. At this point ice is formed, the solid phase of water. If the temperature is allowed to increase, the molecules will once again begin to vibrate faster and faster.

Answer:Ice is water in its solid form. Ice keeps its shape, even if it's removed from the container. The molecules in ice are locked into place and cannot move or slide past one another, but they do vibrate a little bit.

Explanation:

Mark & Sally were in lab and they were working on a chemical reactions experiment. They mixed 2 liquids together and a white sold color appeared. What can Mark & Sally conclude as their observation?

A chemical change
B physical change

Answers

Answer:

A chemical change

Explanation:

From the observation, a chemical change has ensued.

A chemical change is one in which new kind of matter is formed. It is always accompanied by energy changes . This process is not easily reversible.

This process depicted by Mark and Sally is chemical change. This reaction is a precipitation reaction since an insoluble solid has been formed. In chemical changes the process is not reversible.

2CO2 + 3H2O + 4Br2

C =

O =

H =

Br =

Answers

Explanation:

2CO2 + 3H2O + 4Br2

C = 2

O = 5

H = 6

Br =8

Which is equal to a temperature of 50 degrees F? 18 degrees C, 46 degrees C, 10 degrees C, 32 degrees C?

Answers

Answer:

10 degrees C

Explanation:

the _ lobe is important in processing visual information.

a. parietal
b. frontal
c. temporal
d. occipital

Answers

Answer:

It's D

Explanation:

High percent yield generally indicates a carefully run experiment.
O True
False

Answers

in my opinion it's true!!!

what is the gel-like part of the eye?

Answers

Answer:

vitreous

Explination:

The vitreous is the gel-like fluid that fills your eye. It's full of tiny fibers that attach to your retina (the light-sensitive layer of tissue at the back of the eye). As you get older, the fibers of your vitreous pull away from the retina.

Answer:

The vitreous

Explanation:

Out of magnesium, iron, calcium, mercury, copper, or aluminum which metal would be the most useful when transporting acids or water solutions? PLEASE HELP!!! Thank you

Answers

May be mercury is the best choice because it would not react with acid
Other Questions
what is the coefficiant of (x^4)( y^3) iterm in the expansion of (x-2y)^7 A golfer aims for a hole that is 120 feet away and, when he hits the golf ball off the ground, its highest point reaches 80 feet up in the air. Noemis team is working together to write the quadratic equation to model the path of the golf ball in graphing form. She calculated the value of a = - 1/90 . Is she correct? The balance of a loan is $2,570 in January, and the monthly payment is $125.50. The relationship between the loan balance, y, and the number of monthly payments made since January, x, can be represented by the equation y = 2,570 - 125.50x. In what months does the loan balance, y, meet the condition, $1,600 < y < $2,000? January February March April May June July August September October November December Can someone please answer my last question, ill post more like it for more points :) You make more than minimum payments before the due dates. You missed a credit card payment in November and paid a late fee. You opened three new credit card accounts in a month. Your employer gave you a raise, so your income increased. The balance on your credit card is close to the credit limit. From the book nothing to envy. What caused Chang-bo to get into trouble with the Ministry for the Protection of State Security? A rectangle has a perimeter of 58 m and a length of 20 m. What isthe width of this rectangle in metres? If the year is 2012, which phrase correctly completes this sentence? Je suis n Brest en 2000. J'habite Brest._______ What is the total number of pencils that Mr. Moretti gives to his studentsif he puts 3 mechanical pencils in each bag? help with khan academy plzzz!!! why did rival candidates become president and vice president ? The number of kids in a school decreased by 20% between last year and this year. Last year there were 80 kids in the school. What is the population this year? If you get stuck, consider making a table. Does anyone else feel empty and like there is no purpose for your soul to be here? Giving brainly to CORRECT answersThe diagram below shows that the colonists formed some of their political views from historical documents.Which idea completes the diagram?Freedom of religionLimited monarchyEconomic freedomSelf-government The length of a rectangle is 1 inch more than 2 times its width. the area of the rectangle is 36 suare inches. what is the lenght of the rectangle. Read the excerpt from Animal Farm.That evening Squealer explained privately to the otheranimals that Napoleon had never in reality beenopposed to the windmill. On the contrary, it was hewho had advocated it in the beginning, and the planwhich Snowball had drawn on the floor of theincubator shed had actually been stolen from amongNapoleon's papers. The windmill was, in fact,Napoleon's own creation. Why, then, asked somebody,had he spoken so strongly against it? Here Squealerlooked very sly. That, he said, was ComradeNapoleon's cunning. He had seemed to oppose thewindmill, simply as a maneuver to get rid of Snowball,who was a dangerous character and a bad influence.Now that Snowball was out of the way, the plan couldgo forward without his interference. This, saidSquealer, was something called tactics. He repeated anumber of times, "Tactics, comrades, tactics!"Squealer explains to the other animals that Napoleonwas never opposed to the windmill. How does thisconflict propel the plot forward?The other animals realize that Squealer andNapoleon are friendsThe other animals realize that Napoleon can betrusted.It changes the way the other animals feel aboutNapoleonIt changes the way the other animals feel about thedogs. Concord Inc. reported total assets of $6399000 and net income of $503000 for the current year. Concord determined that inventory was understated by $137000 at the beginning of the year and $60900 at the end of the year. Ignoring income taxes, what is the corrected amount for total assets and net income for the year Jack can long-jump 195% of his height with a running start. If Jack is 50 inches tall, how far can he long-jump? According to the Plot Map, what are #3 and #5 ?A. Exposition, Rising Action B. Climax, Resolution C. Rising Action, Falling Action D. Exposition , Resolution Find four consecutive integers whose sum of 456