Answer:
Ammonia is an Arrhenius base and a Brønsted-Lowry base.
Explanation:
An Arrhenius base is any substance which, when it is dissolved in an aqueous solution, produces hydroxide (OH^-), ions in solution. An aqueous solution is a solution that has water present in it.
A Bronsted-Lowry base is a substance that accepts a proton, that is, a hydrogen ion (H^+).
Looking at the equation above, ammonia satisfies both characteristics. We can see that when ammonia is dissolved in water, hydroxide ions is produced in the solution. Hence it is an Arrhenius base. Similarly, the hydroxide ion is formed when ammonia accepts a proton. This is a characteristic of a Brownstead-Lowry base. Hence ammonia is both an Arrhenius base and a Brownstead-Lowry base.
Answer:
c. 9.94 g
Explanation:
From the question,
Using
mt = m₀e⁻kt.................... Equation 1
Where mt = mass of the leaf remaining in the bag, m₀ = original mass of leave that was placed in the bag, k = decay constant, t = time.
Given: m₀ = 33 g, k = 0.04, t = 30 days.
Substitute into equation 1
mt = 33(e⁻(0.04ˣ30))
mt = 33e⁻¹²/¹⁰
mt = 33/e¹²/¹⁰
mt = 33/3.320
mt = 9.94 g.
Hence the right answer is c. 9.94 g
Answer: Most of the stars in the universe are main sequence stars — those converting hydrogen into helium via nuclear fusion. A main sequence star may have a mass between a third to eight times that of the sun and eventually burn through the hydrogen in its core. Over its life, the outward pressure of fusion has balanced against the inward pressure of gravity. Once the fusion stops, gravity takes the lead and compresses the star smaller and tighter.
Temperatures increase with the contraction, eventually reaching levels where helium is able to fuse into carbon. Depending on the mass of the star, the helium burning might be gradual or might begin with an explosive flash.
Answer:
0.42mole
Explanation:
Given parameters:
Number of atoms of titanium = 2.5 x 10²³atoms
Unknown:
Number of moles = ?
Solution:
To solve this problem, we must understand that a mole of any substance contains the Avogadro's number of particles.
6.02 x 10²³ atoms makes up 1 mole of an atom
2.5 x 10²³ atoms will contain 
= 0.42mole
