How many sig figs are in 70030?

Which of the following statements is true?

Verizon [17]

A is automatically wrong since protons have a +1 charge. B is wrong since it states electrons have no charge. C is wrong since it says electrons have no charge. Therefore we are left with D.

7 0

4 years ago

You are given a 0.25 M solution of sodium citrate. How would you make 3 mL of a 25-fold dilution?

Eva8 [605]

Answer:

By adding 2.88 milliliter of water to the 0.12 milliliter of 0.25 M solution of sodium citrate will give 25-fold diluted solution.

Explanation:

25 fold dilution means that the concentration of solution is reduced by one by twenty fifth times of the original solution.

Fold - dilution = $\frac{V}{V'}$

V =Volume of original solution before dilution

V' = Total Volume of solution after dilution

V = x

V'= 3

$\frac{1}{25}=\frac{x}{3}$

x = $\frac{3}{25}mL$

Total Volume of solution after dilution = V + y

y = Amount of solvent added ( here is water)

V + 3 = 3 mL

$\frac{3}{25}mL+y=3mL$

$y=3 mL-\frac{3}{25}mL=2.88 ml$

Volume of water added = 2.88 mL

Volume of original solution = 3 ml - 2.88 ml = 0.12 mL

By adding 2.88 milliliter of water to the 0.12 milliliter of 0.25 M solution of sodium citrate will give 25-fold diluted solution.

5 0

3 years ago

What are Ionic bonds?

bekas [8.4K]

Answer:

this I'd is only left on Indian brainly 2 one is also ban

4 0

2 years ago

Read 2 more answers

URGENT PLEASE HELP!!

Mrac [35]

Answer:

Option C) =O

Explanation:

Ketone is an organic compound with general formula RCOR' ie RC=OR' the C bonding to the O is bonded to two other carbon. R and R'are alky groups

3 0

4 years ago

Read 2 more answers

Ammonia gas (NH3) combines with oxygen gas (O2) to form diatomic nitrogen gas and water vapor. If 4.0 grams of ammonia react, ho

Fantom [35]

Answer:

1.13 L

Explanation:

First, we have to write the chemical equation for the reaction between ammonia gas (NH₃) and oxygen gas (O₂) to give nitrogen gas (N₂) and water (H₂O), as follows:

NH₃(g) + O₂(g) → N₂(g) + H₂O(g)

Then, we have to balance the equation (we write first the coefficient 2 for NH₃ to balance N atoms, then a coefficient of 3 for H₂O to balance H atoms, and finally 1/3 to balance the O atoms):

2 NH₃(g) + 3/2 O₂(g) → N₂(g) + 3 H₂O(g)

In the balanced equation, we can see that 1 mol of N₂ is produced from 2 moles of NH₃. We convert the moles of NH₃ to grams by using its molecular weight (MW):

MW(NH₃) = 14 g/mol N x 1 + (1 g/mol H x 3) = 17 g/mol

grams of NH₃ = 17 g/mol x 2 = 34 g

Thus, we have the stoichiometric ratio:

1 mol of N₂/2 mol NH₃ = 1 mol of N₂/34 g NH₃

To calculate how many moles of N₂ are produced from 4.0 of NH₃, we multiply the mass by the conversion factor:

4.0 g NH₃ x 1 mol of N₂/34 g NH₃ = 0.1176 moles N₂

Finally, we calculate the liters of N₂ gas by using the ideal gas equation:

PV = nRT ⇒ V = nRT/P

We introduce the data in the equation:

T = 32.00°C + 273 = 305 K

P = 2.6 atm

R = 0.082 L.atm/K.mol (is the gas constant)

n= 0.1176 moles

⇒ V = nRT/P = (0.1176 mol x 0.082 L.atm/K.mol x 305 K)/(2.6 atm)

= 1.13 L

3 0

3 years ago