1. Mass number of Lithium-7: 7
Explanation:
- The atomic number of an element is equal to the number of protons inside its nucleus
- The mass number of an element is equal to the number of protons+neutrons inside its nucleus
The nomenclature "Element-X", where X is the number of protons+neutrons, is used to indicate the mass number of the isotope. Therefore, an isotope of LIthium-7 has a mass number of 7.
2. An isotope of lithium-8 contains 5 neutrons
Explanation:
Lithium is the third element of the periodic table, so its atomic number is 3, which means that it has 3 protons.
In this problem, we have an isotope of lithium-8, which means that it has a mass number of 8: so, the sum of neutrons+protons in its nucleus is 8:
where p is the number of protons and n the number of neutrons. However, we also know that for lithium p=3, so we can find the number of neutrons:
Ah hah ! There's an easy way and a hard way to do this one.
If it's OK with you, I'm gonna do it the easy way, and not even
talk about the hard way !
First, let's look at a few things in this question.
-- "gravitational force between a planet and a mass"
This is just a complicated way to say "How much does the mass weigh ?"
That's what we have to find.
-- If we know the mass, how do we find the weight ?
Multiply the mass by the acceleration of gravity there.
Weight = (mass) x (gravity) .
-- Do we know the acceleration of gravity on this dark mysterious planet ?
We do if we read the second line of the question !
It's right there ... 8.8 m/s² .
-- We know the mass. We know gravity. And we know that
if you multiply them, you get the weight (forced of gravity).
I'm pretty sure that you can do the rest of the solution now.
weight = (mass) x (gravity)
Weight = (17 kg) x (8.8 m/s²)
Multiply them:
Weight = 149.6 kg-m/s²
That complicated-looking unit is the definition of a Newton !
So the weight is 149.6 Newtons. That's the answer. It's choice-A.
It's about 33.6 pounds.
When this mass is on the Earth, it weighs about 37.5 pounds.
But when it's on this planet, it only weighs about 33.6 pounds.
That's because gravity is less on this planet. (8.8 there, 9.8 on Earth)
Answer:
I cant see the paper very well
Explanation:
Soil texture<span> is a </span>classification<span> instrument used both in the field and laboratory to determine soil classes based on their physical texture. Soil texture can be determined using qualitative methods such as texture by feel, and quantitative methods such as the hydrometer method.
For</span> soil sample contains 20 percent sand, 10 percent clay, and 70 percent silt we have silty loam <span>present in the sample.</span>
Answer:
This is the definition of slope.
Step-by-step explanation:
The formula for slope is:
m(slope) = (y2 - y1)/(x2 - x1)
This shows the difference in y, which is rise, divided by the different in x, or run.