They have high melting and boiling points and are hard and brittle
Answer:
Ethanol
Explanation:
2 C atoms and a single OH group.
Formula: C2H5OH
Answer:
Explanation:
1. A measure of how quickly velocity is changing is the acceleration
Acceleration is the rate of change of velocity with time. The rate at which a body is changing its velocity is known as the acceleration.
It is measured in the unit m/s²
2. Speed in a given direction is the velocity
Velocity is a vector quantity which measures the magnitude of motion in a specific direction. It is simply speed in a given direction.
When we say a motorcycle travels at the rate of 5m/s due east, we are describing the velocity of such body.
3. Force that resists moving one object against another is the friction
Friction is a force that opposes motion. It prevents a body from moving.
4. Measure of the pull of gravity on an object Weight
Weight is a measure of the amount of gravitational force on a body. It is mathematically expressed as;
W = mg
W is the weight, m is the mass and g is the acceleration due to gravity
5 Tendency of an object to resist a change in motion is inertia
Inertia is the tendency of body to resist change in motion. It is the ability of a body to remain in a perpetual state of rest.
6 Size is the magnitude
Electrons in an atom can be classified as core electrons and valence electrons. Valence electrons are those electrons which are present in valence shell and participates in bond formation. While, Core electrons are all remaining electrons which are not present in valence shell, hence not take part in bonding.
Atomic number of Selenium (Se) is 34 hence it has 34 electrons with following electronic configuration;
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁴
From electronic configuration it is found that the valence shell is 4, and the number of electrons present in valence shell are 6. So,
Core Electrons = Total Electrons - Valence Electrons
Core Electrons = 34 - 6
Core Electrons = 28
Result:
There are 28 core electrons in Selenium.
The velocity would be 0.5 i think
