Answer:
Cleaning products like bleach, oven sprays, liquid laundry capsules and toilet cleaners are chemicals. So are paints, glues, oils, pesticides and medicines. Most of the chemicals you use at home aren't dangerous if you use them properly. However, some chemicals need more careful handling than others.
Answer:
Explanation:
The frequency and the wavelength of a wave are related by the equation
where
v is the speed
f is the frequency
is the wavelength
For the sound wave in this problem, we have
f = 634 Hz (frequency)
(wavelength)
Therefore, the speed of the wave is
The speed of sound in air depends on the temperature according to the equation
where T is the temperature.
In this problem, we know the speed, so we can calculate the temperature:
Answer:
C. Aluminum
Explanation:
Aluminum has 5.9858 ionization energy
Boron has 8.298 ionization energy
Silicon has 8.1517 ionization energy
Carbon has 11.2603 ionization energy
The correct answer is Mercury
Explanation:
In a circular object or spherical object such as a planet, the diameter is calculated by drawing a straight line from one side of the sphere to the other. This measure is the double of the radius (distance from the center to any side). In the case of planets, these differ not only in properties but also in size, which makes them have different diameters.
For example, the diameter of Earth is approximately 12,700 km, while the diameter of Jupiter (the largest planet) is almost 143,000 km. In this context, the planet with a diameter that is approximately the same that the distance from one coast to the other in the U.S. is Mercury because the diameter of this planet is almost 4879 kilometers and the distance from the West coast to the East coast is approximately 4828 kilometers, although this distance varies depending on the location.
Answer:
0.42 g
Explanation:
<u>We have: </u>
pH = 12.10 (25 °C)
V = 800.0 mL = 0.800 L
To find the mass of sodium hydroxide (NaOH) we can use the pH:
![pOH = -log ([OH^{-}])](https://tex.z-dn.net/?f=%20pOH%20%3D%20-log%20%28%5BOH%5E%7B-%7D%5D%29%20)
![[OH]^{-} = 10^{-pOH} = 10^{-1.90} = 0.013 M](https://tex.z-dn.net/?f=%5BOH%5D%5E%7B-%7D%20%3D%2010%5E%7B-pOH%7D%20%3D%2010%5E%7B-1.90%7D%20%3D%200.013%20M)
Now, we can find the number of moles (η) of OH:
![\eta = ([OH]^{-})*V = 0.013 mol/L * 0.800 L = 1.04 \cdot 10^{-2} moles](https://tex.z-dn.net/?f=%5Ceta%20%3D%20%28%5BOH%5D%5E%7B-%7D%29%2AV%20%3D%200.013%20mol%2FL%20%2A%200.800%20L%20%3D%201.04%20%5Ccdot%2010%5E%7B-2%7D%20moles)
Since we have 1 mol of OH in 1 mol of NaOH, the number of moles of NaOH is equal to 1.04x10⁻² moles.
Finally, with the number of moles we can find the mass of NaOH:
<em>Where M is the molar mass of NaOH = 39.9 g/mol </em>
Therefore, the mass of sodium hydroxide that the chemist must weigh out in the second step is 0.42 g.
I hope it helps you!
