Answer:
It is a chemical change.
Explanation:
When the electricity is off, the filament cools down to its original physical state. This physical process repeats every time the light is turned on and off. However, if the bulb is cracked and air is introduced, the oxygen in the air reacts with the tungsten filament which then undergoes a chemical change.
False. The closest Shell to the nucleus is called the “1 shell” valence electrons are the electrons of an atom that are located at the uppermost shell of the electron, which is called the valance shell. it has 7 electrons in its second shell which is its outer most shell and so it will have 7 valance electrons.
Answer:
Acids have a high concentration of [H⁺] ions
Explanation:
In order to know about the acids, a solution is acidic when pH < 7
As pH is lower than 7, the pOH > 7
When pH = 7, solution is neutral
When pH is greater than 7, solution is basic
pH = - log [H⁺]
pOH = - log [OH⁻]
Imagine a solution of pure HCl 0.2 M
HCl → H⁺ + OH⁻
[H⁺] = 0.2 M → pH = - log 0.2 → 0.69
pH + pOH = 14
pOH = 14 - 0.69 = 13.31
10^-pOH = [OH⁻] → 10⁻¹³°³¹ = 4.89ₓ10⁻¹⁴
In conclussion [H⁺] > [OH⁻]
Answer: First, here is the balanced reaction: 2C4H10 + 13O2 ===> 8CO2 + 10H2O.
This says for every mole of butane burned 4 moles of CO2 are produced, in other words a 2:1 ratio.
Next, let's determine how many moles of butane are burned. This is obtained by
5.50 g / 58.1 g/mole = 0.0947 moles butane. As CO2 is produced in a 2:1 ratio, the # moles of CO2 produced is 2 x 0.0947 = 0.1894 moles CO2.
Now we need to figure out the volume. This depends on the temperature and pressure of the CO2 which is not given, so we will assume standard conditions: 273 K and 1 atmosphere.
We now use the ideal gas law PV = nRT, or V =nRT/P, where n is the # of moles of CO2, T the absolute temperature, R the gas constant (0.082 L-atm/mole degree), and P the pressure in atmospheres ( 1 atm).
V = 0.1894 x 0.082 x 273.0 / 1 = 4.24 Liters.
Explanation:
Answer:
tundra, rainforest, desert, grasslands, taiga, deciduous forest
Explanation:
