Do periods run left to right on the periodic table

Darwin's theorized that three conditions were necessary for natural selection to occur, which of the following is NOT one of the

Mekhanik [1.2K]

Answer:

The correct option is: stable environment

Explanation:

According to the Darwin's theory, natural selection is the concept by which all the small useful variations of traits are preserved.

According to Darwin, there are three <u>necessary and sufficient conditions</u> for the occurrence of natural selection:

1. struggle for existence

2. variation

3. inheritance

These conditions are said to be necessary because if these conditions are not satisfied then natural selection does not occur.

These conditions are said to be sufficient because if these conditions are satisfied, then natural selection will most definitely occur.

8 0

3 years ago

What is the sum of 16+ -20?

mr Goodwill [35]

Answer:

-4

Explanation:

PLz give me brainliest I worked hard thank u

6 0

3 years ago

Read 2 more answers

Water is Carried to the leaves by stomata

tiny-mole [99]

Answer:

please explain further and i maybe can help you

Explanation:

5 0

3 years ago

How many nickel atoms are in a nickel coin with a mass of 3.95g

lyudmila [28]

Answer:

4.05 × 10²² atoms

Explanation:

Step 1: Given data

Mass of nickel: 3.95 g

Step 2: Calculate the moles corresponding to 3.95 g of nickel

The molar mass of nickel is 58.69 g/mol.

3.95 g × (1 mol/58.69 g) = 0.0673 mol

Step 3: Calculate the atoms in 0.0673 moles of nickel

We will use Avogadro's number: there are 6.02 × 10²³ atoms of nickel in 1 mole of atoms of nickel.

0.0673 mol × (6.02 × 10²³ atoms/1 mol) = 4.05 × 10²² atoms

5 0

3 years ago

A 125g metal block at a temperature of 93.2 degrees Celsius was immersed in 100g of water at 18.3 degrees Celsius. Given the spe

nikitadnepr [17]

Answer:

$\large \boxed{34.2\, ^{\circ}\text{C}}$

Explanation:

There are two heat transfers involved: the heat lost by the metal block and the heat gained by the water.

According to the Law of Conservation of Energy, energy can neither be destroyed nor created, so the sum of these terms must be zero.

Let the metal be Component 1 and the water be Component 2.

Data:

For the metal:

$m_{1} =\text{125 g; }T_{i} = 93.2 ^{\circ}\text{C; }\\C_{1} = 0.900 \text{ J$^{\circ}$C$^{-1}$g$^{-1}$}$

For the water:

$m_{2} =\text{100 g; }T_{i} = 18.3 ^{\circ}\text{C; }\\C_{2} = 4.184 \text{ J$^{\circ}$C$^{-1}$g$^{-1}$}$

$\begin{array}{rcl}\text{Heat lost by metal + heat gained by water} & = & 0\\q_{1} + q_{2} & = & 0\\m_{1}C_{1}\Delta T_{1} + m_{2}C_{2}\Delta T_{2} & = & 0\\\text{125 g}\times 0.900 \text{ J$^{\circ}$C$^{-1}$g$^{-1}$} \times\Delta T_{1} + \text{100 g} \times 4.184 \text{ J$^{\circ}$C$^{-1}$g$^{-1}$}\Delta \times T_{2} & = & 0\\112.5\Delta T_{1} + 418.4\Delta T_{2} & = & 0\\112.5\Delta T_{1} & = & -418.4\Delta T_{2}\\\Delta T_{1} & = & -3.719\Delta T_{2}\\\end{array}$

$\Delta T_{1} = T_{\text{f}} - 93.2 ^{\circ}\text{C}\\\Delta T_{2} = T_{\text{f}} - 18.3 ^{\circ}\text{C}$

$\begin{array}{rcl}\Delta T_{1} & = & -3.719\Delta T_{2}\\T_{\text{f}} - 93.2 ^{\circ}\text{C} & = & -3.719 (T_{\text{f}} - 18.3 ^{\circ}\text{C})\\T_{\text{f}} - 93.2 ^{\circ}\text{C} & = & -3.719T_{\text{f}} + 68.06 ^{\circ}\text{C}\\4.719T_{\text{f}} & = & 161.3 ^{\circ}\text{C}\\T_{\text{f}} & = & \mathbf{34.2 ^{\circ}}\textbf{C}\\\end{array}\\\text{The final temperature of the block and the water is $\large \boxed{\mathbf{34.2\, ^{\circ}}\textbf{C}}$}$

3 0

3 years ago