<span>A characteristic feature of diatom cells is that they are encased within a unique cell wall made of silica (hydrated silicon dioxide) called a frustule.</span>
The atomic number of the product decrease by one in the d) positron emission and the e) electron capture radioactive decay. These radioactive decays are two of three common forms of the Beta Decay which occurred when the proton released a positron and a neutron emitted an electron<span>. The Beta Decay can increase or decrease the atomic number.</span>
We all struggle in some subjects, you do badly when you don't try, and sometimes we try and can't get the answer, I'll help with that. :)
The first answer is CO2(g), CO2 is a gas, and all gas have... 4) No definite shape, no definite volume.
A piece of ice, a block of wood, and a ceramic cup are solids. They have shapes that do not change and volumes that can be measured. Any matter that is a solid has a definite shape and a definite volume.
A liquid takes the shape of what holds it, besides a flat surface, which will just evidently, take the shape of a flat surface. A liquid has a definite volume, because the volume of a liquid is constant because forces of attraction keep the particles loosely together.
Gases attempt to fill a container of any shape or size. Therefore, it has no definite shape.
There are forces of attraction among the particles in all matter, therefore, it has no definite volume.
The second question might become easier with the explanation above. A liquid has a definite volume because the forces of attraction are loosely together! Therefore, it has a definite volume, but it will take the shape of it's container.
This means... Yes! 2) It retains its original volume but changes shape.
This one is easy. To convert one gram of a solid at its normal heating point to a liquid at the same temperature, is the 1) Heat of Vaporization.
Heat of Vaporization is the amount of heat energy required to convert one gram of a substance from a liquid to a gas.
The third question, the molecules for H20, in a solid phase are always in an geometric and arranged pattern.
Most solids are arranged in geometric and arranged patterns, and since H20 is not in its indefinitely shaped liquid phase, it has a definite shape and thus, retains a repeating (geometric) pattern.
(Note- Some solids like wax or rubber do not have an arranged or geometric pattern.)
The “average of a kinetic energy” is defined as the vitality of movement of particles of a framework.
Or in simpler terms, “energy motion”.
So when temperature increases, the average kinetic energy of a molecule(s) 1) increases.
The number of mole of HCl needed for the solution is 1.035×10¯³ mole
<h3>How to determine the pKa</h3>
We'll begin by calculating the pKa of the solution. This can be obtained as follow:
- Equilibrium constant (Ka) = 2.3×10¯⁵
- pKa =?
pKa = –Log Ka
pKa = –Log 2.3×10¯⁵
pKa = 4.64
<h3>How to determine the molarity of HCl </h3>
- pKa = 4.64
- pH = 6.5
- Molarity of salt [NaZ] = 0.5 M
- Molarity of HCl [HCl] =?
pH = pKa + Log[salt]/[acid]
6.5 = 4.64 + Log[0.5]/[HCl]
Collect like terms
6.5 – 4.64 = Log[0.5]/[HCl]
1.86 = Log[0.5]/[HCl]
Take the anti-log
0.5 / [HCl] = anti-log 1.86
0.5 / [HCl] = 72.44
Cross multiply
0.5 = [HCl] × 72.44
Divide both side by 72.44
[HCl] = 0.5 / 72.4
[HCl] = 0.0069 M
<h3>How to determine the mole of HCl </h3>
- Molarity of HCl = 0.0069 M
- Volume = 150 mL = 150 / 1000 = 0.15 L
Mole = Molarity x Volume
Mole of HCl = 0.0069 × 0.15
Mole of HCl = 1.035×10¯³ mole
<h3>Complete question</h3>
How many moles of HCl need to be added to 150.0 mL of 0.50 M NaZ to have a solution with a pH of 6.50? (Ka of HZ is 2.3 x 10 -5 .) Assume negligible volume of the HCl
Learn more about pH of buffer:
brainly.com/question/21881762
