Answer:
electroluminescence is a production of light by the flow of electrons, as within certain crystals. An example is at most resataurants with a bright sign that either says open or closed.
Explanation:
Answer: 8556 mm, or 855.6 cm (8560 mm to 3 sig figs)
Explanation: Convert mm to cm by dividing by 10 (1cm/10mm)
Find the area of the foil face in cm^2 (30cm*0.2020cm) = 0.606 cm^2
Calculate the volume occupied by 1.40 kg of foil in cm^3. 1.40kg = 1400g
1.400g/(2.7 g/cm^3) = 518.5 cm^3 for 1.40 kg Au
Volume = Area (of the face) * Length
We want Length:
Length = Volume/Area
L = (518.5 cm^3/0.606 cm^2)
L = 855.6 cm (8556 mm) Round to 3 sig figs (856 cm and 8560 mm)
1)The branch of science concerned with the substances of which matter is composed and it is a study of matter.
2)It helps you understand the world around you,chemistry helps you to understand product labels and etc.
3)You find chemistry in daily life in the foods you eat,the air you breathe,cleaning chemicals and etc.
4) Physical,Analytical, Biochemistry,Organic and inorganic chemistry.
Answer:
0.062mol
Explanation:
Using ideal gas law as follows;
PV = nRT
Where;
P = pressure (atm)
V = volume (L)
n = number of moles (mol)
R = gas law constant (0.0821Latm/molK)
T = temperature (K)
Based on the information provided;
P = 152 Kpa = 152/101 = 1.50atm
V = 0.97L
n = ?
T = 12°C = 12 + 273 = 285K
Using PV = nRT
n = PV/RT
n = (1.5 × 0.97) ÷ (0.0821 × 285)
n = 1.455 ÷ 23.39
n = 0.062mol
PH is defined as the negative log of Hydrogen ion concentration. Mathematically we can write this as:
![pH=-log[H^{+}]=-log[H_{3}O]](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%7B%2B%7D%5D%3D-log%5BH_%7B3%7DO%5D%20%20)
We are given the concentration of
. Using the value in formula, we get:
![pH=-log[1.8*10^{-4}]=3.745](https://tex.z-dn.net/?f=pH%3D-log%5B1.8%2A10%5E%7B-4%7D%5D%3D3.745%20)
Therefore, the pH of the solution will be 3.745
