Answer:
C) 1 and 3
Explanation:
A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells. ... Arranged this way, groups of elements in the same column have similar chemical and physical properties, reflecting the periodic law.
Answer:
CCl2=CCl2
Explanation:
Recall that the individual dipole moments in a symmetrical molecule cancel out each other thereby making the overall molecule to be non polar.
CCl2=CCl2 contain individual polar bonds but the molecule is highly symmetrical thus its dipole cancel out and the molecule has no overall dipole moment, hence CCl2=CCl2 has a dipole moment of zero .
In gamma decay, no change in proton number occurs, so the atom does not become a different element
The answer is A - cytosine and adenine
Answer:
The system gains 126100 J
Explanation:
The heat can be calculated by the equation:
Q = nxCxΔT, where Q is the heat, C is the heat capacity,n is the number of moles and ΔT is the variation of temperature (final - initial). The number of moles is the mass divided by the molar mass, so:
n = 250/4 = 62.5 mol.
The system must be in thermal equilibrium with the surroundings, so if the temperature of the surroundings decreased 97 K, the temperature of the system increased by 97 K, so ΔT = 97 K
Q = 62.5x20.8x97
Q = 126100 J
