Answer:
metals
Explanation:
Approximately three-quarters of all known chemical elements are metals. The most abundant varieties in the Earth's crust are aluminum,... Gold (Au), chemical element, a dense lustrous yellow precious metal of Group 11 (Ib), Period 6, of the periodic table.
Answer:
The right choice is c. Water molecules have a weakly positive hydrogen end.
Explanation:
The unequal sharing of electrons in water molecule gives a slight negative charge near its oxygen atom ( see image below) and a slight positive charge near its hydrogen atoms. A neutral molecule that has a partial positive charge at one end and a partial negative charge at the other, it is a polar molecule.
so
a. Water molecules have a nonpolar bond.
It is wrong choice because water has polar bond .
b. Water molecules have a weakly positive oxygen end.
Also, a wrong choice due to water molecule gives a slight negative charge near its oxygen atom.
c. Water molecules have a weakly positive hydrogen end.
This is the right choice.
d. Water molecules have two oxygen and two hydrogen atoms
It is wrong choice because water has one oxygen and two hydrogen atoms
<u>So, the right choice is</u>
c. Water molecules have a weakly positive hydrogen end.
If a sample is packed poorly, the sample will not heat evenly and will take longer to melt.
The optimum pH of formic acid - formate buffer is 3.75
<h3>What is pH? </h3>
- pH is a measure of how acidic/basic water is. The range goes from 0 - 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.
- pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.
What is Buffer ?
A substance or a solution which resists any changes in pH, when acid or alkali is added to it.
pH = pKa + log[base] / [acid]
Considering equimolar concentration of acid and base
pH = 3.75 + log(x)/(x)
pH = 3.75 + log (1)
pH = 3.75 + 0
pH = 3.75
Hence,
The optimum pH of formic acid - formate buffer is 3.75
Learn more about pH here:brainly.com/question/16036689
#SPJ4
Answer:
The answer to your question is 41.6 g of AgCl
Explanation:
Data
mass of NH₄Cl = 15.5 g
mass of AgNO₃ = excess
mass of AgCl = 35.5 g
theoretical yield = ?
Process
1.- Write the balanced chemical reaction.
NH₄Cl + AgNO₃ ⇒ AgCl + NH₄NO₃
2.- Calculate the molar mass of NH₄Cl and AgCl
NH₄Cl = 14 + 4 + 35.5 = 53.5 g
AgCl = 108 + 35.5 = 143.5 g
3.- Calculate the theoretical yield
53.5 g of NH₄Cl -------------------- 143.5 g of AgCl
15.5 g of NH₄Cl ------------------- x
x = (15.5 x 143.5) / 53.5
x = 2224.25 / 53.5
x = 41.6 g of AgCl