Write 657000 in scientific notation.

Which product forms from a reaction between calcium (Ca) and phosphorus

IrinaVladis [17]

Answer:

A

Explanation:

3 0

2 years ago

Read 2 more answers

How many total atoms are in 0.680 g of P₂O5?

Ludmilka [50]

Answer: 2.88× $10^{24}$ atoms $P_{2}O_{5}$

Explanation: First, using stoichiometry, we must convert this from grams to moles, then from moles to atoms.

1. For the first step, we should also look at the periodic table to find the molar mass of the compound, then use that as the denominator.

$0.680g P_{2} O_{5} *\frac{1molP_{2} O_{5} }{141.948gP_{2} O_{5} } =4.79mol P_{2} O_{5}$

2. Now that it is converted to moles, we must convert it to atoms by multiplying it by Avogadro's number.

$4.79molP_{2} O_{5} *\frac{6.022X10^{23} }{1mol} =2.88*10^{24}$

With this information, we know that there are $2.88X10^{24}$ total atoms in 0.680 grams $P_{2} O_{5}$ .

I hope this helps! Pls give brainliest!! :)

8 0

2 years ago

A chemist adds of a calcium sulfate solution to a reaction flask. Calculate the mass in grams of calcium sulfate the chemist has

Elanso [62]

The given question is incomplete. The complete question is:

A chemist adds 0.85 L of a 0.0050M calcium sulfate to a reaction flask. Calculate the mass in grams of calcium sulfate the chemist has added to the flask. Round your answer to significant digits.

Answer: The mass in grams of calcium sulfate the chemist has added to the flask is 0.58 g

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

$Molarity=\frac{n}{V_s}$

where,

n = moles of solute

$V_s$ = volume of solution in L

moles of $CaSO_4$ = $\frac{\text {given mass}}{\text {Molar mass}}=\frac{xg}{136g/mol}$

Now put all the given values in the formula of molarity, we get

$0.0050=\frac{x}{136\times 0.85}$

$x=0.58 g$

Therefore, the mass in grams of calcium sulfate the chemist has added to the flask is 0.58 g

7 0

3 years ago

The adult blue whale has a lung capacity 5.0\times10^3 5.0 Ã 10 3 l. calculate the mass of air (assume an average molar mass of

Andre45 [30]

For this item, we need to assume that air behaves like that of an ideal gas. Ideal gases follow the ideal gas law which can be written as follow,
PV = nRT
where P is the pressure,
V is the volume,
n is the number of mols,
R is the universal gas constant, and
T is temperature

In this item, we are to determine first the number of moles, n. We derive the equation,
n = PV /RT
Substitute the given values,

n = (1 atm)(5 x 10³ L) / (0.0821 L.atm/mol.K)(0 + 273.15)
n = 223.08 mols

From the given molar mass, we calculate for the mass of air.
m = (223.08 mols)(28.98 g/mol) = 6464.9 g

<em>ANSWER: 6464.9 g</em>

8 0

3 years ago

An unknown compound was found to be soluble in concentrated sulfuric acid; however, the 2,4-DNP, chromic acid, and potassium per

Alecsey [184]

Explanation:

2,4-DNP is negative: aldehyde and ketone absent

Chromic acid is negative: alcohol absent.

KMnO4 test negative: alkene absent

The only positive result is for Fe(OH)2.

Nitro group-containing compounds react with ferrous hydroxide to give amine and ferric hydroxide red ppt. Hence given compound contains the nitro group (-NO2).

5 0

3 years ago