What is the recommended PH levels for the human body?

Warning signs are sometimes placed on aerosol cans to prevent people from throwing them into a fire.

bagirrra123 [75]

Answer:

I'm sorry I don't know the answer

4 0

2 years ago

Read 2 more answers

Round 0.0645 g to 2 significant figures

Hoochie [10]

The number of significant figures within a number are the amount digits that are required to specify a number to a certain degree of accuracy. In the number, 0.0645 g, the 6 is the most significant figure and 4 is the second most significant figure. Therefore, rounding to two significant figures yields 0.064g.

5 0

3 years ago

Small quantities of oxygen can be prepared in the laboratory by heating potassium chlorate, KClO3(s).

pychu [463]

Answer:

26.110 grams of O2 produced.

Explanation:

Calculate the amount of moles in KClO3 by dividing the amount of grams given by the atomic weight of the substance.

To get the atomic weight: K = 39.098, Cl = 35.45, O = 15.999, and there are 3 molecules of Oxygen, so multiply 15.999 by three.

39.098 + 35.45 + (15.999 * 3) = 122.548.

66.7g / 122.548 atomic mass = 0.544 moles.

The ratio of moles of KClO3 to moles of O2 is 2 to 3.

$\frac{2}{3}$ = $\frac{0.544}{y}$

Cross multiply to get 1.632 = 2y. Y = 0.816, meaning 0.816 moles of O2 will be produced.

Convert this into grams by multiplying by the atomic weight of O2 (15.999 * 2 = 31.998).

0.816 * 31.998 = 26.110 grams of O2 produced.

3 0

3 years ago

What is the molarity of the Ca(OH)2 solution if 32.00 mL of Ca(OH)2 requires 16.08 mL of a 2.303 M solution for complete titrati

amm1812

Answer:

For this problem we just need to remember the equation and that the volume is always in liters: MaVa=MbVb

Ma= 1.338 mol/L Va= 18.75 mL= 0.01875 L Mb= x Vb=24.73 mL= 0.02473 L

So now we can plug into the equation and solve:

1.338 mol/L * 0.01875 L= x mol/L * 0.02473 L

This is a two step process: stoichiometry and using the answer from the first part to plug and chug it into the Molariy equation.

First step: setup the stoichiometry problem:

3.1171 g Na2CO3 * (1 mol/106 g) * (2 mol HCl/ 1 mol Na2CO3)= mol HCl

Second step: Molarity equation

Molarity= moles HCl/ L M= mol HCl/0.04027 L

For the third problem, you will just use the same equation as the first: MaVa= MbVb

Ma=0.57 M Va= x L Mb= 0.875 M Vb= 23.83 mL= 0.02383 L

0.57 M * x L= 0.875 M * 0.02383 L

With this equation, we want to find the moles of NaOH by using the molarity equation first then because MaVa= MbVb, we know that the number of moles has to be equal.

0.75 M= x mol/ 0.0227 L mol NaOH = 0.75 M *0.0227 L mol NaOH= 0.017025

So next, we can set it to the mass of the acid using this equation: Molar Mass= mass/ moles

Molar Mass= 3.6 g/ 0.017025 mol

And with that you will find the molar mass of HX, and even determine what X is.

Explanation:

hope I helped

8 0

3 years ago

In carbon dioxide, London dispersion forces are the only intermolecular forces of

LUCKY_DIMON [66]

Answer:

true

Explanation:

CO has two C-O bonds. The dipoles point in opposite directions, so they cancel each other out. Thus, although CO₂ has polar bonds, it is a nonpolar molecule. Therefore, the only intermolecular forces are London dispersion forces.

8 0

3 years ago