Answer:
Date Significance Soviet Union Mission
August 21, 1957 First intercontinental ballistic missile (ICBM) R-7 Semyorka
October 4, 1957 First artificial satellite First signals from space Sputnik 1
November 3, 1957 First dog in orbit (Laika) Sputnik 2
January 31, 1958 First US satellite, detection of Van Allen radiation belts
Explanation:
Do you have a picture of where you go this question from?
Answer:
Mass of solute = 0.0036 g
Explanation:
Given data:
Concentration of Cl⁻ = 15.0 ppm
Volume of water = 240 mL
Mass of Cl⁻ present = ?
Solution:
1 mL = 1 g
240 mL = 240 g
Formula:
ppm = mass of solute / mass of sample ×1,000,000
by putting values,
15.0 ppm = (mass of solute / 240 g) ×1,000,000
Mass of solute = 15.0 ppm × 240 g / 1,000,000
Mass of solute = 0.0036 g
Electronegativity is your answer.
Ca + Cl2 = CaCl₂
A synthesis <span>reaction.</span>