Divide velocity by the wavelength.
Answer:
molecular compound
Explanation:
it has two or more nonmetal elements and are covalently bonded
Answer : The pressure of the helium gas is, 1269.2 mmHg
Explanation :
To calculate the pressure of the gas we are using ideal gas equation:
where,
P = Pressure of 
gas = ?
V = Volume of gas = 210. mL = 0.210 L (1 L = 1000 mL)
n = number of moles = 0.0130 mole
R = Gas constant = 
T = Temperature of gas = 
Putting values in above equation, we get:
Conversion used : (1 atm = 760 mmHg)
Thus, the pressure of the helium gas is, 1269.2 mmHg
Answer:
Number of protons = 82
Explanation:
Given data:
Atomic number of Pb = 82
Mass number of Pb-207 = 207
Number of protons = ?
Solution:
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
Atomic number of Pb = number of protons or electrons
82 = number of protons or electrons
Mass number = Number of protons + number of neutron
207 = 82 + number of neutron
Number of neutrons = 207 - 82
Number of neutrons = 125
The nervous system sends signals to the muscles to shiver when our body temperature begins to drop to a lower than normal temperature. the slight movement of the muscles will work to bring temperature back to homeostasis
