A(n) __________ occurs when the moon enters the umbral shadow of the earth without being entirely immersed in it.

How the relative density of a substance is related to the density calculate the density of iron if its relative density is 2 and

il63 [147K]

Answer:

How the relative density of a substance is related to the density calculate the density of iron if its relative density is 2 and a density of water is 2gcm -3

R.d= relative density of substance/ relative density of water

R.d= 2/2

R.d= 1gcm-3

Explanation:

5 0

3 years ago

Rank the following elements by electron affinity, from most positive to most negative EA value.

LenKa [72]

Answer:

Explanation:

Bromine >Tellurium > Phosphorus > Helium > Sodium

Electron affinity of Bromine , Tellurium , Phosphorus are positive , of helium is zero and of sodium is negative .

3 0

2 years ago

In water, hydrogen bonds are best described as _____.

Elina [12.6K]

Answer: Option D) covalent bonds between water molecules

In water, hydrogen bonds are best described as covalent bonds between water molecules

Explanation:

The hydrogen bonds between water molecules are covalent bonds because they are formed when oxygen attract the lone electron in hydrogen, thus resulting in the formation of a partially negative charge on the oxygen atom and a partially positive charge on two hydrogen atoms

Thus, the sharing of electrons between oxygen and hydrogen atoms is responsible for the covalent bonds between water molecules

7 0

2 years ago

For the elementary reaction NO3 + CO → NO2 + CO2 the molecularity of the reaction is ________, and the rate law is rate = ______

blagie [28]

Answer: For the elementary reaction $NO_3+CO\rightarrow NO_2+CO_2$ the molecularity of the reaction is 2, and the rate law is rate = $k[NO_3]^1[CO]^1$

Explanation:

Order of the reaction is defined as the sum of the concentration of terms on which the rate of the reaction actually depends. It is the sum of the exponents of the molar concentration in the rate law expression.

Elementary reactions are defined as the reactions for which the order of the reaction is same as its molecularity and order with respect to each reactant is equal to its stoichiometric coefficient as represented in the balanced chemical reaction.

Molecularity of the reaction is defined as the number of atoms, ions or molecules that must colloid with one another simultaneously so as to result into a chemical reaction. Thus it can never be fractional.

For elementary reaction $NO_3+CO\rightarrow NO_2+CO_2$ , molecularity is 2 and rate law is $rate=k[NO_3]^1[CO]^1$