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3 years ago

Because of their large mass and charge, alpha rays are the least penetrating and least dangerous.

1 answer:

6 0

This is true.
Beta and Gamma radiation are the most dangerous because they can penetrate the skin, and damage the cells inside.

Alpha is the least dangerous.

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How many grams are in 3.78 x 10^22 molecules of SO2?

Vesnalui [34]

X2 is the answer help me and I will help you

6 0

3 years ago

2. A/an _______ bond allows metals to conduct electricity. A. ionic B. metallic C. covalent D. atomic

lisov135 [29]

The appropriate answer is b. A metallic bond allows metals to conduct electricity. Metallic bonds are formed by atoms of metals in which the outer electrons of the atoms from a common electron cloud. In metallic bonding the atoms are not used up in the actual bond but are shared so they are free to move about to conduct electricity. Electrons in the other bond types are held in place in the molecule an are not free to move about so they cannot conduct electricity.

7 0

3 years ago

Read 2 more answers

An aqueous KNO3 solution is made using 72.5 g of KNO3 diluted to a total solution volume of 2.00 L. Calculate the molarity, mola

Sonja [21]

Answer:

The molarity is 0.359 $\frac{moles}{L}$

The molality is 0.354 $\frac{moles}{kg}$

The mass percent of the solution es 3.45%

Explanation:

Molarity is a unit of concentration that indicates the amount of moles of solute that appear dissolved in each liter of the mixture. It is determined by:

$Molarity (M)=\frac{number of moles of solute}{volume}$

Being:

K: 39 g/mole
N: 14 g/mole
O: 16 g/mole

The molar mass of KNO₃ is:

KNO₃= 39 g/mole + 14 g/mole + 3*16 g/mole= 101 g/mole

You can apply the following rule of three: if 101 grams of KNO₃ are present in 1 mole, 72.5 grams in how many moles are present?

$moles of KNO_{3}=\frac{72.5 grams*1 mole}{101 grams}$

moles of KNO₃= 0.718

So you have:

moles of KNO₃= 0.718
volume= 2 L

Applying this quantity in the definition of molarity:

$molarity=\frac{0.718 moles}{2 L}$

Molarity= 0.359 $\frac{moles}{L}$

The molarity is 0.359 $\frac{moles}{L}$

Molality is a way of measuring the concentration of solute in solvent and indicates the amount of moles of solute in each kilogram of solvent.

Then the molality is calculated by:

$Molality=\frac{moles of solute}{mass of solvent in kilograms}$

Density is defined as the property that matter, whether solid, liquid or gas, has to compress in a given space. That is, it is the amount of mass per unit volume. So, if the density of 1.05 g / mL for the solution indicates that in 1 mL of solution there are 1.05 grams of solution, in 2000 mL (where 2L = 2000 mL, because 1 L = 1000mL) how much mass is there?

$mass=\frac{2000 mL*1.05 grams}{1 mL}$

mass= 2100 grams

Since mass solution = mass water + mass KNO₃

then mass water = mass solution - mass KNO₃

Being mass solution 2100 grams and mass KNO₃ 72.5 grams, and replacing you get: mass water= 2100 grams - 72.5 grams

mass water= 2,027.5 grams

Then, being:

moles of KNO₃= 0.718
mass of solvent in kilograms= 2.0275 kg (being 2,027.5 grams= 2.0275 kilograms because 1,000 grams= 1 kilogram)

Replacing in the definition of molality:

$molality=\frac{0.718 moles}{2.0275 kg}$

molality= 0.354 $\frac{moles}{kg}$

The molality is 0.354 $\frac{moles}{kg}$

The mass percent of a solution is the number of grams of solute per 100 grams of solution. Then the mass percent is the mass of the element or solute divided by the mass of the compound or solute and the result of which is multiplied by 100 to give a percentage.

$mass percent=\frac{mass of solute}{mass of solution} *100$

So, in this case:

$mass percent=\frac{72.5 grams}{2100 grams} *100$

mass percent= 3.45 % KNO₃ by mass

The mass percent of the solution es 3.45%

3 0

3 years ago

why is H2SO4 considered as strong acid? What colour does it give with phenolphthalein and methyl orange?

marta [7]

Answer:

H2SO4 (sulphuric acid) is considered a strong acid because it's H+ ions completely dissociates or ionizes in a water. When reacted with phenolphthalein is colourless because phenolphthalein doesn't react with acids, only strong bases and when reacted with methyl orange, it changes from orange to red.

Explanation:

4 0

3 years ago

What are some other type of chemical reactions? What makes them different?

Elenna [48]

Combustion, Synthesis, Decomposition, acid/ base neutralization, double displacement, single displacements.
The difference between all of this is that they don’t have the same outcome, combustion combines, synthesis comes together, decomposition breaks down, single displacement trades place, double displacement switch place,

8 0

2 years ago