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3 years ago

Express in scientific notation. Choose the answer with the proper number of significant figures.

Chemistry

1 answer:

bazaltina [42]3 years ago

3 0

Answer:

4.5 times 10 = 45

Explanation:

"Non-zero digits are always significant. Any zeros between two significant digits are significant. A final zero or trailing zeros in the decimal portion ONLY are significant."

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When writing a formula for a compound having a transition metal in it, _____.

Stella [2.4K]

Answer:

it is always necessary to use the roman numeral as the assigned charge of the metal.

Explanation:

This is so that one would know which Transition metal is being used. For example copper (II) would be Cu²+

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3 years ago

A sample of 3.62 moles of diphosphorous trioxide is

Sindrei [870]

$H_3PO_3$ $2H_3PO_3$ $2H_3PO_3$ $P_2O_3$ Answer:

Explanation:

This question is about stoichiometry. From the balanced equation $P_2O_3 + 3H_2O$ ⇒ $2H_3PO_3$ , we see that 3 moles of water is needed to react with 1 mole of $P_2O_3$ .

This means that, to fully react 3.62 moles of $P_2O_3$ , we would need 3*3.62 or 10.86 moles of water. However, we only have 6.31 moles, so water is the limiting reactant.

Since 3 moles of water react with 1 mole of $P_2O_3$ , 6.31 moles of water can fully react with 6.31÷3 or 2.1033 moles of $P_2O_3$ .

From the balanced equation, we see that every mole of $P_2O_3$ reacted gets you 2 moles of $2H_3PO_3$ . Therefore, 2.1033 moles of $P_2O_3$ would give you approximately 4.21 moles of $H_3PO_3$ .

5 0

2 years ago

Suppose you put a whole antacid tablet in one glass of water and a crushed antacid tablet in another glass containing the same a

iogann1982 [59]

The crushed tablets would stop bubbling/fuzzing first because it has a smaller surface area which means that it would dissolve before the uncrushed tablets which has a larger surface area.

3 0

3 years ago

What is another name for a beta minus (B-) particle?

pentagon [3]

<span>electron, I believe.
</span>

6 0

3 years ago

Write the steps for calculating molar mass.

Marizza181 [45]

Answer:

Explanation:

1) Find number of each of the type of atom that is present in the compound, using the chemical formula .

2) Then multiply number of atoms of each element that is present in the compound with the atomic weight of each of the element

3) Add everything together and add the units (grams/mole ) after the number

Let finds that of water

Chemical formula of water is (H20 )

hydogens atoms= 2

oxygen atom= 1

Atomic weight for Hydrogen= 1

Atomic weight for Oxygen= 16

Total number of atoms of Hydrogen from the formula (H2O)= 2

Total number of atoms of Oxygen from the formula (H2O)= 1

the molar mass=

Hydrogen: ( 2 x 1)= 2

Oxygen: ( 1 x 16)= 16

Add together= (16+2)

= 18

Then add the unit, we have(18 g/mol.)

5 0

3 years ago