Metals are found on the left-hand side of the periodic table. True or False

The Sun is a yellow star that's both average in brightness and temperature and is classified as

Roman55 [17]

Answer:

Classifying stars according to their spectrum is a very powerful way to begin to understand how they work. As we said last time, the spectral sequence O, B, A, F, G, K, M is a temperature sequence, with the hottest stars being of type O (surface temperatures 30,000-40,000 K), and the coolest stars being of type M (surface temperatures around 3,000 K). Because hot stars are blue, and cool stars are red, the temperature sequence is also a color sequence. It is sometimes helpful, though, to classify objects according to two different properties. Let's say we try to classify stars according to their apparent brightness, also. We could make a plot with color on one axis, and apparent brightness on the other axis, like this:

Explanation:

7 0

2 years ago

What is first and second element of the periodic table?

stira [4]

The elements on the periodic table are listed in increasing atomic number.

Hydrogen is the first element, and has an A.N. of 1. Also, its very interesting how it doesn't need 8 valence electrons to be stable.

The second element is Helium, which has an A.N (atomic number) of two.

7 0

2 years ago

Read 2 more answers

You apply 100.0 of force to a machine. The machine applies 20.0 N of force to the load. What is the mechanical advantage of the

rjkz [21]

MA= output force/input force
MA= 100N/20N
MA= 50

5 0

2 years ago

_____________ is an acronym used to refer a family of iron alloys.

Daniel [21]

FeNi or NiFe is an acronym used to refer a family of iron alloys.

<h3>What is alloy?</h3>

An alloy is a mixture of chemical elements that contains at least one is a metal.

<h3>Alloy of iron</h3>

The alloy of iron-nickel can be abbreviated as FeNi, which implies iron-nickel.

where;

Fe stands for iron
Ni stands for Nickel

Thus, FeNi or NiFe is an acronym used to refer a family of iron alloys.

Learn more about iron alloys here: brainly.com/question/24842164

5 0

1 year ago

EXTRA POINTSSS 1. A solution at 25 degrees Celsius is 1.0 × 10–5 M H3O+. What is the concentration of OH– in this solution?

AlekseyPX

Answer:

Concentration of OH⁻:

1.0 × 10⁻⁹ M.

Explanation:

The following equilibrium goes on in aqueous solutions:

$\text{H}_2\text{O}\;(l)\rightleftharpoons \text{H}^{+}\;(aq) + \text{OH}^{-}\;(aq)$ .

The equilibrium constant for this reaction is called the self-ionization constant of water:

$K_w = [\text{H}^{+}]\cdot[\text{OH}^{-}]$ .

Note that water isn't part of this constant.

The value of $K_w$ at 25 °C is $10^{-14}$ . How to memorize this value?

The pH of pure water at 25 °C is 7.
$[\text{H}^{+}] = 10^{-\text{pH}} = 10^{-7}\;\text{mol}\cdot\text{dm}^{-3}$
However, $[\text{OH}^{-}] = [\text{H}^{+}]=10^{-7}\;\text{mol}\cdot\text{dm}^{-3}$ for pure water.
As a result, $K_w = [\text{H}^{+}] \cdot[\text{OH}^{-}] = (10^{-7})^{2} = 10^{-14}$ at 25 °C.

Back to this question. $[\text{H}^{+}]$ is given. 25 °C implies that $K_w = 10^{-14}$ . As a result,

$\displaystyle [\text{OH}^{-}] = \frac{K_w}{[\text{H}^{+}]} = \frac{10^{-14}}{1.0\times 10^{-5}} = 10^{-9} \;\text{mol}\cdot\text{dm}^{-3}$ .

8 0

2 years ago