<h3>
Answer: Si (choice D)</h3>
This is the element Silicon.
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Explanation:
First convert each percentage to its decimal form.
For example, 92.2297% converts to 0.922297 after moving the decimal point two spots to the left.
After doing that, multiply those decimal values with their respective atomic mass unit (amu) values.
- 27.9769 * 0.922297 = 25.8030109393
- 28.9765 * 0.046832 = 1.357027448
- 29.9738 * 0.030872 = 0.9253511536
Then we add up the results
25.8030109393 + 1.357027448 + 0.9253511536 = 28.0853895409
That rounds to about 28.085
Then look at the periodic table to see the atomic mass of Cobalt (Co), Aluminum (Al), Nickel (Ni) and Silicon (Si). The mass values listed in the periodic table are weighted averages of all the isotopes. The units for the mass are still in amu.
- Cobalt = 58.933
- Aluminum = 26.982
- Nickel = 58.693
- Silicon = 28.085
We have a match with silicon, showing that <u>choice D</u> is the final answer.
Answer:
Strong acids are assumed 100% dissociated in water- True
As a solution becomes more basic, the pOH of the solution increases- false
The conjugate base of a weak acid is a strong base- true
The Ka equilibrium constant always refers to the reaction of an acid with water to produce the conjugate base of the acid and the hydronium ion- True
As the Kb value for a base increases, base strength increases- true
The weaker the acid, the stronger the conjugate base- true
Explanation:
An acid is regarded as a strong acid if it attains 100% or complete dissociation in water.
The pOH decreases as a solution becomes more basic (as OH^- concentration increases).
Ka refers to the dissociation of an acid HA into H3O^+ and A^-.
The greater the base dissociation constant, the greater the base strength.
The weaker an acid is, the stronger , its conjugate base will be.
Answer:
Explanation:
The period law state that when elements are listed in order of their atomic numbers, the elements fall into recurring groups, so that there is a recurrence of similar properties at regular intervals.
Na and K in the periodic table fall into the same group, this is because they both have one electrons in their outermost shell.
Na 11 -1s2 2s2 2p6 3s1
K 19 - 1s2 2s2 2p6 3s2 3p6 4s1
They share similar chemical and physical properties. Na and K are very reactive metals, they can loose/donate their outermost electron to non metals in other to attain stable octet state.
The form ionic compound when they react with non metals.
Answer:
D (The last answer)
Explanation:
In a transverse wave, particles oscillate perpendicular to the direction of wave motion.
In a longitudinal wave, the oscillations of particles are parallel to the direction of propagation.
