Answer:
metallic bond
Explanation:
Metallic bonds are the attraction between a positive metal ion and the electrons surrounding them.
This bond is found in metals and their alloys. They are interatomic forces.
- In this bond, a positive nuclei joins with all other closely packed atoms in the lattice and the electron cloud formed by losing their outermost shell electrons.
- Most of the physical properties of metals is due to this bond type.
When repeated measurements of the same quantity are very close to one another they are termed as precise measurements.
<u>Explanation:
</u>
An experiment is repeated two to three times and the outcomes were checked to have similar values to attain precision of the measurements. The accuracy and precision are the important in attaining correct measurements.
The accuracy is the closest true value obtained from the measuring instrument. But to get precise results, the measurements were taken repeatedly and then analyzed whether the values obtained are similar or varying significantly.
If the repeatedly measured values are very close to one another that means the measured quantities are precisely taken. All the values are precise in nature.
First convert the inches cubed to centimeters cubed. Looking at the rate, we can write 2 inches cubed = 2 * 16.39 cm cubed = 32.78 cm cubed.
The equation for density is D = M/V, where D is the density, M is the mass, and V is the volume. Substitute the values into the equation:
0.242 = M/32.78
Multiply by 32.78 on both sides.
The mass is about 7.93 grams.
Answer:
pH= 9.2
Explanation:
Henderson hasselbach equation
pKa= log Ka= log (4.9 x 10^-10)=9.3
![pH=Pka+log \frac{[A-]}{[HA]}](https://tex.z-dn.net/?f=pH%3DPka%2Blog%20%5Cfrac%7B%5BA-%5D%7D%7B%5BHA%5D%7D)
![pH=9.3+log \frac{[CN-]}{[HCN]}](https://tex.z-dn.net/?f=pH%3D9.3%2Blog%20%5Cfrac%7B%5BCN-%5D%7D%7B%5BHCN%5D%7D)
![pH=9.3+log \frac{[0.64 M]}{[0.83 M]}](https://tex.z-dn.net/?f=pH%3D9.3%2Blog%20%5Cfrac%7B%5B0.64%20M%5D%7D%7B%5B0.83%20M%5D%7D)
pH= 9.2